The 22-year-old sustained an anterior cruciate ligament (ACL) injury during his first training session after the Club World Cup on Tuesday, and has since had a scan and operation.

ACL injuries typically rule players out for between six and nine months.

Colwill was a near ever-present for Chelsea last season in the Premier League, starting 35 of their 38 matches as they qualified for the Champions League.

The England international also played a major role as a substitute in the Conference League final and during the Club World Cup, as Chelsea won their first two major trophies under the current ownership.

When asked if Chelsea needed to sign another defender to replace Colwill at his media conference before friendlies against Bayer Leverkusen and AC Milan, Maresca said: “It depends – we will wait and see.

“You know in our way, how important Levi has been. I spoke with him yesterday and I told him that if we achieve what we achieved last year, it is also because of him – and he was a main player for us.”

Chelsea’s alternative defensive options are new signing Jorrel Hato, Tosin Adarabioyo, Benoit Badiashile, Trevoh Chalobah and Josh Acheampong.

The 22-year-old started the shock 3-0 win over Paris Saint-Germain in New Jersey’s MetLife Stadium, which crowned the Blues became world champions for the next four years in Fifa’s expanded global tournament.

Asked whether Chelsea can build on that success to win either the Premier League or Champions League, Colwill replied: “Yeah, definitely.

He added: “I said at the start of this tournament that our plan is to win it and people looked at me as if I was crazy. So I’m going to say the exact same thing now going into the Premier League and Champions League.

“This is the biggest trophy I’ve ever won. I think the Club World Cup will be bigger than the Champions League and we were the first team to win it.

“It was a statement victory and, in the future, if we keep winning trophies then everyone will give us the love that we deserve.

“But we’ll only know that in he future. I think we’re ready and we’ll see next season.”

Chelsea finished fourth in the Premier League last season and won the Conference League in an impressive first season under the leadership of manager Enzo Maresca.

It has been a significant year for Chelsea co-owners Todd Boehly and Clearlake Capital, after they earned their first real success since buying the club in 2022.

Their signing of a large number of young players on lengthy contracts has proven unpopular with some within the football community, but Colwill believes Chelsea now have a winning team capable of emulating the past.

“We’re a team and that’s in the Chelsea identity. You stick together no matter what. I think players like John Terry, Frank Lampard, Didier Drogba, they started that and we’re carrying it on,” he said.

“They were all amazing players, the best players who won a lot but we’ve got the best players in our team – young players for sure – and that’s our plan: to win the biggest trophies for Chelsea.

“We’re definitely capable of doing it. I think we’ve shown that. Everyone said that PSG were the best team in the world but we won 3-0.”

The England centre-back, 22, has played 25 times for the Blues this season in Maresca’s first season in charge.

They are in the hunt for the Champions League places, sitting fifth in the Premier League table.

Colwill spoke to BBC Football Focus about a range of topics – and you can watch the interview in full on BBC One at 12:00 BST on Saturday.

BBC Sport has some of the highlights here.

‘Blessed’ to play under Maresca

Italian Maresca, 45, was Manchester City assistant boss before winning promotion to the Premier League with Leicester last season.

He swapped the King Power Stadium for Stamford Bridge in the summer.

“I think with Maresca, the way he thinks about football is light years above everyone else,” said Colwill.

“Of course, I have been blessed with loads of different managers that have been amazing.

“He is pushing me to understand football in a different way. That’s why I’m very blessed to play football under him and learn as much as possible.”

Colwill has also played under Carlos Corberan, Graham Potter, Roberto de Zerbi, Mauricio Pochettino, Gareth Southgate and Lee Carsley.

‘Animals’ from Chelsea’s academy

Colwill has been at Chelsea since under-nine level.

“I came through with the likes of Jamal Musiala, Tina Livramento, Myles Peart-Lewis, Lewis Bate. My age group was amazing. You can see the difference between Chelsea academy players and others,” he said.

“The treatment you get at Chelsea, they turn you into animals.

“These players coming up now are different. I don’t know what’s been done there.

“Shim [Shim Mheuka] just made his debut for us.

“Ty [Tyrique George], he’s just electric and you’ve got Josh [Acheampong] who’s going to be one of the best defenders.”

The centre-back revealed the extra meaning his goal in the recent 4-0 win over hometown club Southampton had for him.

“I don’t think many people understand as a kid that’s all I dreamed about scoring against Southampton for Chelsea,” he said.

“Growing up I wasn’t the biggest fan of Southampton. All my mates were Southampton fans and they’d be getting on to me.

“Before I joined Chelsea, I was in Southampton’s academy and they were pushing me in the development a bit.

“The love Chelsea gave me when they came in for me, there were levels to it.”

Huddersfield ‘formed me into the man I am’

Image source: Getty Images

Image caption: Levi Colwill impressed at Huddersfield in the Championship

Colwill’s first experience of first-team football was for then Championship side Huddersfield on loan in 2021-22.

The Terriers finished third and lost the play-off final 1-0 to Nottingham Forest – with Colwill scoring an own goal.

“They formed me into the man I am today,” he said. “I picked up the values of life being in the changing room with different players.

“I was 18, I was still a young boy. Being in the first-team changing room with amazing players.

“We were driving together and I think that’s what made me believe in having such a strong changing room. I thought we were amazing.

“I loved every part of it from scoring in the Champ to losing in the play-off final, but I wouldn’t change anything because that’s how I make my journey.”

The following season he went to Brighton as they finished sixth in the Premier League, their best-ever finish.

“Brighton was top,” he said.

“De Zerbi came in, we didn’t get on at the start, but now he’s like a father figure to me.

“He was amazing, he broke my character first and then made me back up to be a player I couldn’t imagine being before.”

Living ‘dream’ of playing for England

Image source: Getty Images

Image caption: Levi Colwill has played four times for the England senior team

Colwill played for England at various youth levels before making his senior debut in 2023 and has won four caps so far.

“It’s a dream to be in there and hopefully I’ll be picked,” he said of Thomas Tuchel’s first England squad.

“To go and play for my country again, you can never take that feeling away.

“Every time you play for them something grows in you that you want to play again.”

Colwill was part of the England team who won the Under-21 European Championship in 2023..

“A few of the boys have been in the first-team squad with me, we know what it takes to try and win trophies,” he said.

“Hopefully, in the future we can win a trophy for England.”

On his role with Sholing FC

Colwill is an associate director with seventh-tier Sholing FC, a team based in a suburb of Southampton.

He was a mascot in the 2014 FA Vase final when Sholing beat West Auckland Town at Wembley.

Three of his uncles have played for Sholing and his brother JJ currently does too.

“It’s another opportunity for young kids who maybe have been released from an academy who can believe in themselves and start playing football,” said Colwill of his project.

“I think it’ll be an amazing opportunity for them to maybe break into the first team.

“There’s so many amazing players out there that haven’t been given an opportunity.”

The 20-year-old has been a key part of Mauricio Pochettino’s squad in pre-season after helping England win the European Under-21 Championship.

“It’s always been an easy decision,” Colwill said. “As I’ve grown up, all I’ve known is Chelsea. I’ve spoken with the manager and he’s given me reassurance, that trust I æneeded.

“He’s spoken with me not just as a player but as a person. It’s made a big difference.”

Colwill has been at the club since the age of eight but has spent the past two seasons starring on loan at Huddersfield and Brighton.

“Levi is an outstanding player who has risen to every challenge in his career so far,” said co-sporting directors Laurence Stanley and Paul Winstanley.

“We are thrilled he will remain at Chelsea for years to come.”

The deal includes an option to extend his stay by a further 12 months when the six-year contract concludes.