The Spurs boss will soon be without three key players - captain Heung-Min Son and midfielders Yves Bissouma and Pape Sarr - as they jet off to mid-season international tournaments.

Top scorer Son will be at the Asian Cup with South Korea, while Bissouma and Sarr will play for Mali and Senegal respectively at the Africa Cup of Nations. Spurs could be without the trio for all of January and potentially early February.

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Their departures - combined with the injuries to James Maddison, Micky van de Ven and Rodrigo Bentancur - will once again leave Tottenham short. So is the January transfer window arriving at a good time for Postecoglou?

"Yeah, if we get the outcomes it will be," he exclusively tells Sky Sports. "But it's going to be a challenging month for us because you're talking about three players in Pape, Biss and Sonny who have been very important to what we're trying to build.

"We've got Maddison, Van de Ven and Rodrigo Bentancur - really significant players who are missing - so fingers crossed the guys we've got at the moment stay healthy through that period.

"It's going to be a challenging period and January is always a difficult transfer window to get things done particularly quickly, so I think we're preparing ourselves for that."

Postecoglou reveals he has been in contact with Spurs chairman Daniel Levy and new technical director Johan Lange over the club's January plans.

"All of those things are in place," the Australian says. "We don't have daily meetings because that's their department. Johan's [Lange] got his department and he talks with Daniel [Levy] and all of the other key personnel, and I'll get in the loop when you get the significant moments of potentially some progress in certain areas.

"But yeah, the planning is under way but obviously you need multiple parties to be involved and agree on something, and that's not always easy."

Identifying a new centre-back is at the heart of those plans, with Postecoglou confirming it is a "priority" January signing after admitting the sale of Davinson Sanchez following the closure of the summer English transfer window had backfired.

Since the Colombian's exit to Galatasaray in September, Spurs' lack of cover at centre-back has been exposed. Van de Ven, Eric Dier and Ashley Phillips are all injured, while Cristian Romero has only recently returned from a three-game suspension meaning full-backs Ben Davies and Emerson Royal have been deployed at centre-back.

"When you think about it," Postecoglou says, "we let Davinson Sanchez go after the window closed. We kind of knew we were taking a bit of a risk; we couldn't get the extra centre-back that we were trying to get in, and for the early part of the year that was fine.

"But once we lost Micky [van de Ven], and Eric Dier's had some issues as well, we don't have another centre-back.

"Young Ash Phillips had just joined the club, so it's fair to say that we can't run the risk of that happening again, so that's obviously a priority for us in January.

"But again, we've got to get the right person. It's not just about bringing another body in, it's about getting the right one in and hopefully that'll happen."

Sky Sports News reported last week that Everton's Jarrad Branthwaite, Crystal Palace's Marc Guehi and Nice's Jean-Clair Todibo are defensive targets for Spurs.

All three players are aged 23 or under as Tottenham concentrate on signing young top talent.

Asked whether he wants to sign young and hungry players, Postecoglou replies: "Yeah, because that's what we're trying to build at the moment.

"Even Vic [Guglielmo Vicario], he's only 26 for a goalkeeper and the only one we've kind of signed who isn't in that bracket but I still think he's got the best in front of him is Madders [James Maddison], but all the rest are all young.

"Guys like Pape Sarr, Destiny [Udogie], Pedro [Porro] and [Dejan] Kulusevski - who both [Porro and Kulusevski] became permanent [in the summer] - they're all in their early 20s, so we're in the first phase of building something.

"I think when you've got young guys and you start building something and they grow together, I think it gives you more chance of having sustained success down the road."

Postecoglou will be hoping his first January transfer window at Tottenham will be as pivotal as his first winter window at Celtic, when he signed the likes of Matt O'Riley, Reo Hatate and Daizen Maeda.

Those signings, which inspired a strong second-half of the season to win the Scottish Premiership, were part of a squad overhaul that Postecoglou is once again trying to pull off at Spurs.

"For us, it's about constantly evolving this squad," he says. "We've had one window, we're going to need multiple windows to get the squad to where we want it to.

"Our ambitions are to play European football and we're going to need a more robust squad - all of those kind of things factor into it."

Despite wanting to bolster his squad in the upcoming window, Postecoglou admits there is the "possibility" of player departures in January - but there could be an exit from his coaching staff to deal with.

Postecoglou's assistant Chris Davies is being targeted by Swansea for their managerial vacancy. The Championship club are preparing to make another approach to Tottenham for the 38-year-old, despite an initial approach being rejected by Spurs last week.

"You don't want to lose important staff and it's been great working with Chris [Davies] for this last six months," Postecoglou says.

"He's been a big part of what we're trying to build here along with the other coaches; we've got a really great coaching group. Guys I've never worked with before. I came here by myself, so that's the way I love working and it's been great having Chris here.

"Whenever he decides in the future, whether that's with us or elsewhere, I'm sure it won't be the last time that another club looks at him.

"You want good people, and if you've got good people, then you're going to attract attention - I'd much rather that than no one looking at the people we have in the building."

Tottenham are certainly attracting plenty of attention this season thanks to Postecoglou's attacking football.

Sky Sports' Jamie Redknapp believes the 58-year-old has transformed Tottenham from the Premier League's most unwatchable team to its most watchable. And such is their entertainment value right now, fellow Sky Sports pundit Jamie Carragher said on social media that he wants a Spurs season ticket.

"I doubt that very much!" jokes Postecoglou about Carragher's wish. "But look, it's great because it's what I really want to try and make an impact with, that you play the kind of football that even for people who maybe don't support the team, at least enjoy watching it, because I think that's part of the function of football in people's lives.

"I think it's always been a form of escapism for fans that whatever they're going through in a week that they can go there and support their team.

"Every supporter wants to win, but if they've got moments that they can grab onto, even if you don't win, and they can talk about and get excited about, then I think that's certainly the space we want to be in."

Postecoglou's uncompromising philosophy was given its first real test at Spurs after his side endured a five-game winless run.

But the fans, encouraged by the performances in those four losses and one draw, remained behind the team and their faith was rewarded last Sunday as Tottenham eased past Newcastle at home 4-1.

For Postecoglou, the supporters have played their part in getting Spurs through a difficult period.

"It's crucial [the fans' backing] because you know that you're going to go through tough times," Postecoglou says. "There isn't a team that doesn't do that and through those times your supporters can be such a sense of security for you that they will never turn on you, in the sense where you have to really battle to get them to get behind you.

"I think the players have felt that through there. Ultimately, supporters see a group of players who, irrespective of the outcome, they're going in every week and giving their all and not just trying to play good football but actually they're working hard.

"It's been mentioned a few times: running should never be underestimated as a barometer as to how much effort you're putting in. I think the average supporter who sits in the stand, that's what they want to see their team doing. I think this group of players has done that even in those difficult moments."

The pressing stats back Postecoglou up on this. Spurs are top of the charts for pressures in the final third and are second for high turnovers in the Premier League this season.

The intense work rate is one of the hallmarks of 'Angeball' - a positive ideology the Spurs squad have lapped up after the uninspiring football cultivated by his predecessors Jose Mourinho, Nuno Espirito Santo and Antonio Conte.

But even with the players' thirst for free-flowing football, has Postecoglou been surprised by how quickly he has been able to implement his style of play?

"No, I'm not," he says, "because that's what I've done my whole career and obviously working with a higher level footballer here.

"I think the biggest barrier to it is whether the players accept and embrace it, and maybe because it was such a departure from what was happening in the past that maybe the players just thought, 'Okay, well let's just go this way and see where it takes us'.

"I had very little resistance in going that way, and once you get the players' acceptance then it's up to me, and obviously to set up the environment and give them the information to play that way.

"From the first game in pre-season, you could see there were already things happening, that they're understanding and I think then that it takes a life of its own and it grows quickly from there."

Asked whether he felt the players were immediately receptive to his style upon taking charge in the summer, he says: "Yeah, I did. I thought that right from the start. I didn't sense within the room that there was going to be too much initial resistance anyway, until I actually started talking and we started doing things because then they could've turned around and said, 'This is not going to work'.

"But I think they liked what they saw early on in terms of what we were trying to build - not just playing but in our training, and they liked the way that the information was being given to them from all of the coaches, and from there it's just grown."

There has, however, been growing pains that led to Postecoglou admitting after the Newcastle win he had been "too hard" on his players during the five-game winless run amid injuries and suspensions.

Reflecting on that comment four days later, he says: "It's fair to say, I'll always be too hard. I think that's just the way I am and I think for the most part, the players understand that and respond to that.

"Sometimes I kind of sit back and in my own private thoughts think about the fact that we're going through a really difficult time in the toughest competition in the world.

"The guys are giving everything, but again, how you address that, we could have made a million excuses and I think that's where I mean you go a bit easier, but being as hard as I am on them - you always know there's a tipping point if it affects their confidence and belief, but I never sensed that."

That confidence and belief could well be given another stern test in the new year with the international departures of Son, Bissouma and Sarr.

But before that headache of losing three key players arises, Postecoglou just wants to "finish the calendar year strongly" leading to an early assessment of nearly six months in charge at Spurs.

"It's going okay," he says smiling.

He then jokingly adds: "I'm still here, that's the first thing so that's pretty good, which probably defies the odds in many respects.

"I'm enjoying it and I'm just super enthusiastic about what's ahead. I still think there's so much more in this team, we've got so much more to do and so much more to produce.

"I'm loving every minute of it and hopefully it continues for a little while longer."

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