As part of the Future of Football series, Sky Sports investigates the past and present, before making bold predictions for the future, based on data and projections from leading experts...

Is the game becoming more attack-focused?

Arsenal were once renowned for winning 1-0 and that low-scoring habit actually reflects the early era quite well. The Gunners' average score in the Premier League last season was 2.32-1.13.

Premier League goals have been on a general upward trajectory since hitting troughs around 15 years ago - rising from a low of 2.45 per game in 2006/07 to an all-time Premier League high of 2.85 last term.

Runaway teams have been pushing that ratio higher in recent years. Last season, Manchester City (94 goals) and Arsenal (88) scored around three times more than Wolves - who netted a league-low 31 goals.

Why?

Risk and reward has become a buzz phrase in top-flight tactics, often used when referring to teams playing high lines.

Liverpool were renowned for it when their average passing sequences started 45.22m from their own goal-line in 2019/20 and that line edged even higher in 2021/22 - compressing opponents into tighter spaces and relying on the counter-press and defensive line to protect counter threats.

Of course, it can go wrong. On October 4, 2020 it did exactly that when the Reds suffered a 7-2 defeat to Aston Villa - with the home side repeatedly exploiting Liverpool's high line.

Manchester City have recorded even higher seasonal starting distances, but their slower style of play has typically reaped fewer risks, compared with the Reds' more gung-ho approach.

The chart below reveals the league average for starting distance has been creeping upfield in almost every campaign since records began for this metric. So, teams are increasingly of the opinion that rewards outweigh potential risks - with both outcomes resulting in more goals.

The introduction of video-assisted referees (VAR) has helped this trend: teams are protected for offside errors if they hold the defensive line or can win one-on-one foot races. Liverpool caught teams offside a league-topping 142 times during that title-winning campaign, for example - 43 times more than any other team.

But, broadly, teams appear to be leaning towards the idea that rewards outweigh risks when using attacking systems. Players have also become more clinical in front of goal - boosted by other trends, which we will get to...

Shooting from range in decline

The 2009/10 season produced a spike in goals and that campaign coincides with the beginning of a decline in shots attempted from outside the opposition box. Matches produced an average of 12.8 shots per game 13 years ago, but that number dwindled to just 8.4 last season - equating to a 34-per-cent drop.

The chart below reveals most top-half teams last term were among the bottom-half for the proportion of shots taken from outside the box, underlining how the most successful sides are leading the way for restraint from long range.

Why?

What's driving this trend? The clue is in the term: long shot. A shot from distance is far less likely to result in a goal than a shot taken from inside the box. Teams are increasingly maintaining possession and recycling, in order to try and carve clearer opportunities in front of goal - rather than fire shots from distance.

Since 2010/11, only around 3.5 per cent of attempts from outside the penalty box have hit the back of the net, compared with over 15 per cent of shots from inside the box being scored, including penalties.

So, firing closer to goal is more than four times as effective.

Crossing also in decline

Utilising the flanks and firing crosses has been a prominent, attacking approach in the game for a long time - but that trend is also in rapid decline. Back in 2003/04, matches produced an average of 42 open-play crosses per game; last season, that average had plummeted to 24 - equating to a 43-per-cent drop.

Interestingly, many top-half clubs were among the most prolific crossers last term. Notably, Fulham attempted a league-topping 582 open-play crosses to feed aerial hitman Aleksandar Mitrovic. West Ham, also traditionally strong in the air, ranked second in that list.

However, top teams would typically register more crosses - by virtue of having a far greater share of possession in games. When factoring average possession percentage with the number of crosses, those top teams plummet down the rankings.

Liverpool have achieved much success with firing balls into the box from wide using their full-backs - but that approach also began to change towards the end of last season as Trent Alexander-Arnold moved into a hybrid midfield role, increasingly moving into central areas.

Why?

The reason for the decline appears to be linked with the growing trend towards accuracy and efficiency, to avoid ceding possession - with teams playing more directly through central avenues, deploying inverted wingers and making more cut-backs along the ground.

Is the league becoming faster?

People often refer to new signings needing to adapt to the pace of the Premier League. On the eye, the English top-flight appears to have become faster - but has it?

Since only 2020/21, when the tracking metrics changed, the number of sprints per game has risen incrementally every season - rising from 127 in 2020/21, to 129 in 2021/22 and jumping to 134 last season.

Most top clubs sit in the top half for these rankings, with the exception of Manchester City, who play an almost unique brand of possession-based, build-up play.

One of the biggest changes under Eddie Howe's stewardship at Newcastle has been their physical output - having registered a league-topping 5,667 sprints last season. Leeds, under Marcelo Bielsa, literally soared off the chart compared with their rivals, but slipped into second spot under several coaches last term.

Injections of speed was one of the biggest changes during Jurgen Klopp's early days at Liverpool, before his side eased off, amid regular injury crises after festive schedules.

Manchester United manager Erik ten Hag has also encouraged his players to burst from the blocks, with work-rate being core to his philosophy and was arguably the key factor behind Cristiano Ronaldo losing his regular starting berth and, subsequently, leaving the club.

A May 2020 academic study revealed the number of passes per minute in FIFA World Cup finals between 1966 and 2014 increased by around 35 per cent (from 11 to 15 passes) and game speed rose by 15 per cent (from 8.0 m/s to 9.2 m/s).

Based on that trajectory, the number of passes per minute might increase to above 16 and game speed could climb another seven per cent to around 9.8 m/s by 2030.

The study also revealed distance covered at high intensity in the Premier League between 2006/2007 and 2012/2013 increased by 20 per cent, high-intensity actions rose by 50 per cent and total sprint distance climbed by eight per cent.

Based on those numbers, distance covered at high intensity could rise 40 per cent between the 2012/13 season and 2030.

Logically, top teams with above-average possession and a high line would need to run less distance, because they are playing in a more compressed area of the pitch and not chasing the ball, even when factoring the need for movement to find space - but they would be required to sprint back during turnovers.

However, that did not stop Arsenal ranking second in this metric last season, while Tottenham ranked third - driven largely by Antonio Conte's emphasis on work-rate.

Why?

Health and fitness has become a core component for clubs and the modern footballer. Teams are typically turning out younger starting XIs and players are increasingly expected to cover more than one position; full-backs are expected to join attacking phases, forwards are expected to defend and goalkeepers are deployed almost as sweepers.

The evolution of sports science and the quest to maximise estate on the pitch is pushing physical exertions to the limits. Ceiling levels, where only marginal gains can be made, exist - but, for now, there appears to be room for growth as elite footballers are increasingly expected to also perform as elite athletes.

Is tackling a dying art?

Another feature of the game on the wane is tackling - an art which has been in decline for nearly two decades.

Manchester United full-back Aaron Wan-Bissaka has received criticism for his attacking abilities in the past, but few dispute his talent at timing a good tackle.

Fulham midfielder Joao Palhinha received widespread acclaim for his ability to break up play - registering a league-topping 148 tackles last season. Moises Caicedo is in demand and ranks second on that list, Casemiro ranks fourth and Bruno Guimaraes is ninth - all three players represented top-six clubs.

Why?

Lawmakers have clamped down on the sliding tackle and tackles, generally, which has contributed to the decline in committed challenges.

The ongoing debate over how Alexander-Arnold's attacking and defensive abilities compare, along with centre-backs such as John Stones moving into hybrid midfield roles and the focus on ball-playing defenders are factors, too.

Tactically, there also appears to be a shift towards prevention higher up the pitch in midfield, and to nullify threat without going to ground - either positionally, with interceptions or by regaining loose balls.

Are teams pressing more?

Pressing is on the rise, particularly the high press.

Between 2003/04 and last season, reclaiming possession in the final third rose from an average of 4.3 per game to 9.7 - equating to a 125-per-cent hike.

This metric defines when a player recovers the ball in the final third when neither team has possession, or where the ball has been played directly to the player by an opponent and recovers possession for their team - typically achieved with a coordinated team press.

In terms of pressing, Klopp's high-intensity style based around 'gegenpressing' was, arguably, the most influential in the modern era of the English game - but Guardiola also demands similar levels from his side.

Last season, both teams ranked top in this metric, while title-chasing Arsenal ranked third. In fact, all top-half teams in the final league table - bar Fulham and Tottenham - ranked in the top-half of the table for reclaiming possession in the final third.

Of course, these teams typically play more football in the attacking thirds - but the high press has become increasingly important in the recent evolution of tactics.

The metric 'high turnovers' reflects the very same pattern: teams are snatching possession higher up the pitch more frequently.

Why?

This trend runs parallel with teams pushing higher and higher up the pitch. Teams need to reclaim possession and assert immense pressure in the middle and final thirds to prevent dangerous counterattacks - and to keep opponents penned into their defensive thirds.

Starting attacks closer to an opponent's goal is also, obviously, more beneficial than starting deeper on the pitch, while opponents are also often set up incorrectly during turnovers or forced errors.

Tiki-taka and the long ball

It goes without saying that fewer clubs play long balls in the modern era, but what is the scale of that change?

Even as recently as 2009/10, more than 17 per cent of passes were played 'long' - defined as passes exceeding 32m. Last season, that ratio had dropped to just 11.4 per cent - the lowest on record.

The chart below highlights how the top teams almost exclusively record the lowest rates for playing long balls.

Conversely, relegated Leicester perhaps attempted to play the short passing game too much during their quest to secure top-flight survival - with Jamie Vardy spending considerable time on the substitute bench in favour of forwards who are more comfortable receiving the ball to feet.

Top teams still use the long pass for variety. Again, Liverpool are perhaps the most notable with Alisson, Alexander-Arnold and Virgil Van Dijk frequently spraying the ball upfield.

Meanwhile, players such as Crystal Palace centre-back Joachim Andersen have, at times, almost assumed quarterback roles to expand their team's attacking options: Andersen attempted more long passes than goalkeepers Nick Pope, Alisson and Ederson last term.

As a result of teams attempting fewer long passes, passing accuracy has been climbing the other way. The chart below shows how the average passing accuracy in the Premier League during 2009/10 was just 73.1 per cent: that figure has risen to 81.3 per per cent in just 13 years.

The passing-accuracy rankings for Premier League teams last season, shown below, unsurprisingly, are almost inverted to the rankings for the proportion of long passes - with Manchester City achieving a league-high average accuracy of 89.2 per cent.

In contrast, Forest - the most prevalent long ball team, proportionally - rank bottom for accuracy with 72.3 per cent.

For the most part of last season, Brentford played long to Ivan Toney - utilising both David Raya's passing ability and Toney's ability to collect and retain possession - but the Bees still ranked 19th for passing accuracy.

The teams at the lower end of these rankings buck the short-game trend - looking to exploit the very trends aforementioned - often looking to bypass the midfield contests to instigate counters.

Of course, the ability for a goalkeeper to play out from the back has become a compulsory attribute for almost all top clubs, as teams looks to utilise their eleventh player fully.

The stats from last season suggest City reserve goalkeeper Stefan Ortega and Brighton's Jason Steele epitomise this new breed, with both recording the shortest average distances for pass length and the highest pass completion rates.

You can tap the column headers in the interactive table below to also discover that both 'keepers benefited from having above-average passing options at source - which denotes how the teams were set up to play this way.

The chart below clearly tracks the current trend for goalkeepers to retain possession with their pass completion rate hovering at an average of 43 per cent between 2009/04 and 2009/10 before undergoing a sharp rise and hitting soaring to 67 per cent last season - the highest ratio on record.

Why?

The World Cup-winning Spain team in 2010 embodied the benefits of playing tiki-taka, but Guardiola, in particular, arguably expedited a sea-change in the Premier League - with long passes dipping beyond the trend rate shortly after his appointment at City.

Manchester City's success has seen other top teams follow in their wake, while some teams, like Forest, have gone against the grain with relative success. Indeed, Forest adapted during the season to draw opponents and create counter opportunities through their brightest sparks: Morgan Gibbs-White, Brennan Jonson and Danilo.

Hence, every tactical innovation produces a counter-tactic, which prevents the evolution from ever standing still.

Some teams even try to innovate upon similar patterns. On paper, Brighton have played like a 'Big Six' club for several seasons: they achieved a top-six finish for the first time in their top-flight history last term.

Indeed, even tiki-taka masters Manchester City elected to go long[er] at times last season - dismantling title-rivals Arsenal 4-1 in April by frequently passing over the Gunners' high press before hitting a club season-high of 72 long balls against Fulham four days later.

The central tenet behind the rise in short passing and accuracy is identical to all other trends aforementioned: improving efficiency, optimising positioning and utility, retaining possession and increasing options on and off the ball - while nullifying opposition threats with measured risk and reward.

It terms of ball-playing goalkeepers, Guardiola once said: "The less the opponent has [the ball], the less chance they have to score". Perhaps that goes some way towards explaining why some teams appear to be placing more importance on their 'keeper's distribution than shot-stopping skills.

Which positions are in demand?

Forwards have almost exclusively hogged the limelight and loosened clubs' purse strings most. A glance at the list of world-record fees underlines how attackers have typically been the prized assets throughout history.

However, things have been changing domestically. Pep Guardiola jettisoned Joe Hart for a ball-playing goalkeeper when he joined Manchester CIty in 2016 and signed technical midfielders Bernardo Silva and Ilkay Gundogan, before spending over £100m on new full-backs the following summer.

Meanwhile, the two most expensive players in the history of the division are defensive midfielders: Enzo Fernandez (£106.8m) and Declan Rice (£105m) - with both deals completed in the past year.

Players such as N'Golo Kante certainly helped raise the profile of a hard-working midfield destroyer after the France international was widely recognised for his pivotal in Leicester's fairytale title win in 2015/16 before earning a move to Chelsea.

Rampaging full-backs, who could endure running the length of the pitch and fulfil both defensive and attacking duties for 90 minutes became en-vogue - triggering a need for competent defensive midfielders who could drop, cover and counter-press to prevent dangerous counters in transition.

Forwards, in the form of inverted wingers, were still prime estate for some time - peaking with Mohamed Salah and Heung-Min Son sharing the Golden Boot as recently as 2021/22 - often excelling most when playing alongside a central striker who dropped deeper.

Ball-playing defenders and goalkeepers are in demand, as are left-footed players - to eke out every ounce of resource on the pitch. Manchester City switched from deploying a false nine to favouring a traditional No 9 in Erling Haaland - tasked with bullying and exploiting this new breed of defender and other top teams are hunting for equivalents.

The 22-year-old delivered in style with 36 league goals - smashing the record of 34 set by Alan Shearer and Andrew Cole nearly 30 years ago.

Among the top 10 top goalscorers in the Premier League in 2021/22, recognised strikers registered only 50 goals combined. That tally soared to 133 last season - and that excludes Marcus Rashford, who regularly played up top.

The No 9 is back. We could be going full circle.

Why?

Broadly speaking, 'fluidity' summaries these recent trends and clubs appear increasingly willing to invest greater sums on players who can fulfil evolving, tactical requirements - regardless of whether those lie at the glamorous end of the pitch, grafting in the middle or initiating passing sequences and snuffing out danger at the back.

As teams find successful tactical nuances, others imitate, innovate and react, which means the tactical landscape will remain in flux for as long as there is change.

Is there a 4-4-2 renaissance? Is 4-3-3 back for good?

The 4-4-2 formation gets a bad reputation these days, commonly being associated with an old, less-tactical style of play - with long balls 'lumped' up to big strikers. In recent seasons, Burnley and Southampton braved critics and went old-school.

It remains the most used system in the Premier league since 2006/07 - largely because of its dominance in those earlier years.

For context, the 4-4-2 was used 498 times across the division in 2006/07 - no system comes close to matching that dominance in a single campaign since then.

Last season, 13 teams started in a 4-4-2 on 62 occasions in the Premier League. In fact, only the 4-2-3-1, 4-3-3 and 3-4-2-1 were used more frequently this term.

So is it making a comeback? Technically, no - quite the opposite. But, it comes with a caveat.

This season marks a record-low for 4-4-2 since records began. However, that is largely down to Sean Dyche's old Burnley side slipping into the Championship and Southampton deviating to different systems.

Meanwhile, managers have increasingly diversified tactical approaches - despite a notable preference for the 4-2-3-1, which gathered momentum from 2009/10, and the 4-3-3, which began to pick up the following season.

The intriguing factor about whether 4-4-2 could make a comeback is how top-half teams have began to deploy the system again: Aston Villa used it 15 times, Brighton three times, Liverpool, Spurs (both twice) and even Manchester City used it once.

Finally, spare a thought for the 4-5-1 formation, which was used 151 times in 2010/11: it was deployed merely seven times last term.

Why?

Manchester City and Liverpool were once synonymous with the 4-3-3, but both teams strayed from those systems last season, which could be a signal for an imminent drop more broadly across the division - having now reached an all-time usage.

Guardiola deployed a 4-3-3 on 14 occasions in the Premier League last term, having used in 28 times during the previous campaign. Klopp was less deviant, using it 31 times - but had deployed it in every single league game during 2021/22.

But there is also far greater emphasis on systems in and out of possession and positional fluidity, which is seeing a greater variety of starting formations being used than in the earlier days.

Positional fluidity on the rise

Sky Sports' Peter Smith:

Last season, it felt as though conveying a team's line-up in a traditional formation was failing to tell the real story of how that side would shape up in and out of possession during the match. Those familiar labels of 4-3-3, 4-4-2 and 4-2-3-1 are too simplistic for the more complex positional play coaches are requesting from their players.

From early in the season, Oleksandr Zinchenko's role of stepping into midfield from left-back was giving Arsenal an often decisive numerical advantage in midfield. It was a big part of their fine form in the first half of the campaign.

Later, Rico Lewis showed impressive game intelligence at a young age to perform a similar role from right-back for Man City, spending much of matches in-field, forming part of a box midfield alongside Rodri. In the final part of the season, John Stones was able to do the same, either from a starting position at right-back or, even more eye-catchingly, straight out of centre-back.

It was a trend which caught on, with Trent Alexander-Arnold doing the same at Liverpool and Pascal Gross putting his midfield skills from right-back for Brighton. The ultimate aim was to provide extra bodies in the middle of the park and create overloads in important areas. A search for space. For Alexander-Arnold it seemed a solution to emphasise his brilliant ball-playing ability and limit his vulnerability in one-on-one defensive situations.

But it wasn't just on the ball where teams were showing flexibility. It's not a new phenomenon for teams to defend in a different set-up to how they attack but this season it became plainly obvious how sides were switching approach in and out of possession. The classic 4-4-2 was given a revival, with sides banking lines of players in front of opposition teams when they lost the ball and proving hard to break down.

It all makes it tricky for journalists and fans to define a team's set-up in a clear, simple row of numbers. But the complex patterns have added a fascinating element to the tactical battles in the Premier League this season.

So what about the future?

Nothing stands still as tactics evolve. Ball-playing goalkeepers and fielding players with a specific favoured foot in advantageous positions all point towards eking out advantages for passing options and avenues to shoot on goal - and data plays a huge part.

Predictive data is coming to the fore. Data providers Opta are working on a system which presents team shapes in and out of possession - but it can also reveal where players should be positioned during phases of play, layered over where they are actually positioned. It can also quantify how different players combine and affect efficiency.

The data can already predict the likelihood of completing a pass to any team-mate at any given point and the potential attacking threat from each of those options. With these new datapoints, analysts can quantify a player's decision-making by measuring what a player did, but also what they could have done. It can also reveal the proportion of time players assume different roles throughout a game.

With this level of analysis - available instantly and at scale - it appears only a matter of time before predictive data plays a huge part during games and for both pre-match and post-match analysis. As a result, players would be evaluated on how they fare against these predictive models.

Meanwhile, management teams will increasingly study how different player combinations affect overall team chemistry, both broadly and against specific opponents.

Real Analytics is just one company using artificial intelligence to predict how players would perform at clubs, based on their profiles and prospective team-mates - adding a new dimension to simply data-mining their raw stats, which can be skewed according to their league and style.

So, is there a sustainable tactical zenith? One team's evolution and in-game adjustments alters the landscape and an opponent's pre-set plans.

When teams can adapt instantly, even perfectly, pure ability is likely to provide the cutting edge. But the dawn of predictive analysis appears to be under way as teams strive to achieve tactical perfection on the fly.