Bringing an end to years of anticipation over the revolutionary rules overhaul, it was a fascinating first day in Barcelona and one that looked set to be topped by Ferrari as Charles Leclerc and Carlos Sainz filled the top two positions deep into Wednesday, having swapped over at lunch.

But Norris, who had the whole day in the McLaren, found his fastest laps in the closing stages and eventually set the pace with a 1:19.568 - more than half a second clear of Leclerc.

The time was only a second down on the fastest lap from first practice in Barcelona a year ago, a quicker-than-expected result given the cars have been completely redesigned in a bid to improve wheel-to-wheel racing.

New Mercedes team-mates George Russell and Lewis Hamilton, back in an official F1 session for the first time since his crushing and controversial 2021 Abu Dhabi GP defeat, were fourth and fifth, with Hamilton having spent his morning keeping a keen eye on Russell as well as rivals.

One of those was Max Verstappen, whose Red Bull car finally broke cover and looked competitive despite his final position of ninth.

Verstappen, donning the No 1 on an RB18 that featured several innovations, appeared comfortable and racked up 147 laps through the day, more than any individual driver and only behind Ferrari's cumulative team total of 153.

The state of play in Barcelona as F1 2022 begins

After a tempestuous winter for F1, pre-season testing marked the start of a new 2022 season and one that has been eagerly anticipated for some time due to what is one of the biggest regulation changes in the sport's history.

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The new rules are aimed at improving the show and battles through the field, and many team bosses came into the test insisting "nobody knows" what the pecking order will be. But while it is always inadvisable to read too much into an opening day, it looked clear from the outset in Barcelona that the bigger teams from last year have decent bases for cars that will no doubt be evolved in the coming weeks.

Ferrari looked quick throughout the day in an F1-75 car they called "innovative and daring", hoping it can challenge for race wins and ultimately end a trophy drought that has lasted over a decade. Leclerc topped the opening session before Sainz took over and made it a one-two before Norris' surge.

Ferrari were fast but also consistent - a key for the start of testing - and racked up more miles than any other team.

Mercedes, as expected as the reigning eight-time world champions, also started solidly and both Russell and Hamilton quickly got quick laps on the board, albeit not ones that threatened Ferrari.

"We shouldn't be interpreting too much in lap times but better to start solid," said team boss Toto Wolff.

Red Bull, meanwhile, were one of the big talking points from Wednesday, with their 'real' car officially unveiled after the team's launch only featured a show car. The RB18 was called "super impressive" by Sky F1's Ted Kravitz.

"That is a car that has everything," said Ted. "It is something very, very different."

McLaren, who rounded off the top four last year, were quiet compared to their rivals on Day One of testing - until the very end. Norris posted multiple times that would have been good enough for top spot, and his lap at the end of the day on soft tyres suggested there will be plenty more pace over the next two days.

There were also strong starts for Aston Martin and Alpha Tauri - with Sebastian Vettel and Yuki Tsunoda sixth and seventh on the final timesheets - while Williams and Alpine can also take heart from completing over 100 laps.

The only teams not to make a milestone which has become the norm at testing in recent years were Alfa Romeo and Haas, the bottom two from last year enduring a less-than-ideal start to 2022.

Alfa's pair of new signing Valtteri Bottas and reserve driver Robert Kubica managed just 32 laps combined, while Haas suffered a cooling leak and then a damaged floor, kept to only 43 laps.

The two Ferrari-powered teams also had the two slowest times of the day.

Who said what? The key quotes on Day One

Lewis Hamilton, Mercedes
"You would assume that Ferrari perhaps didn't do much development of that car and just put everything into this year's car. So does that mean that they're several months ahead? Or a team is several months ahead of everyone? We'll wait and see."

Max Verstappen, Red Bull
"The car is completely different. I think the RB18 looks good but of course it's about being fast and we hope to see that. Everything worked fine, so it was a good start."