When Fikayo Tomori walks back into Stamford Bridge on Wednesday night, he will have a point to prove, and not just to his former club Chelsea.

But seeing the England international's improvement since he moved to Italy leads to two questions: why did Chelsea let the academy graduate go in the first place, meaning they had to pay £70m for former Leicester defender Wesley Fofana this summer? And why was Tomori left out of the England squad that faced Germany last month instead of the out-of-form Manchester United centre-back Harry Maguire?

Former Chelsea manager Frank Lampard, in charge when Tomori was dropped in 2020, and England boss Gareth Southgate are best placed to answer those dilemmas.

Yet Tomori, who left Chelsea for an initial loan spell at AC Milan in January 2021 before a £24m move the following summer, recognises he has an opportunity to show he has become a "cleverer" defender. Perhaps even a bit more "nasty" after training with team-mate Zlatan Ibrahimovic.

"Every footballer, when you get on the pitch, there's a point to prove," Tomori said, speaking to the English media from Milan before Wednesday's Group E match.

"Obviously coming from Chelsea and being English, there's probably that added motivation. I guess you could say that maybe I've played differently [at AC Milan] or whatever it is.

"[The year] 2020 was difficult, not just for me, obviously there was Covid so it was difficult for everyone. I was just itching to get back on the pitch, itching to be playing, and Milan gave me an opportunity and now I'm here.

"It's just another chance for me to see some familiar faces as well as to, I guess, show how I've developed. I know people have watched the Milan games but going back to Stamford Bridge where it all kind of started, it's another chance to show myself again."

Tomori, who has three England caps, was in the England squad to face Italy for the Nations League match last month but was omitted for the Germany game

How Zlatan has made Tomori more 'nasty'

Milan, who will parade their first Scudetto in 11 years to fans at Wembley's Boxpark on Tuesday evening, are a team in the midst of a renaissance. Tomori has been at the heart of it.

From being "starstruck" when he met legendary former defender Paolo Maldini, who is now AC Milan's technical director, through to being "more concentrated" in matches, Tomori feels like he has been "born into" a team that "takes pride in its defending".

"I think I'm a cleverer defender, whether it's little fouls or positioning yourself," he says. "Being in Italy, players are notorious for being good defenders, being tough to beat, being nasty and stuff like that. It's definitely something I've picked up on - how much pride, how much effort and how much detail is put into every phase of defending."

Whatever doubts Lampard and Southgate may have, the Serie A statistics back up his improvement.

Since his debut, Milan concede an average of 0.8 goals a game with Tomori in the team. But it jumps to an average of 1.3 goals against when he does not play.

Likewise, the win percentage increases from 57% without the Canadian-born player in the side compared to 70% when he is.

Ibrahimovic is currently injured and could not train as the title chase reached its climax last season. But Tomori credits the 41-year-old Swede, who has won the Scudetto twice with Milan in two different spells, with inspiring him on and off the pitch.

"Training against Zlatan, you can't really be too timid because if you are, he'll score 10 goals against you," Tomori adds. "So you have to be a bit tougher, you have to be nasty in a sense. Obviously, having a player like him, who's played against the world's best, is going to make me a better defender.

"He's such a well-rounded figure and having him in a dressing room, especially last season when he was injured for a lot of it, we could still see the impact he had. Just being there with the team, his voice, the way he sees the game, having him around the squad definitely helped us, for sure."

Tomori is enjoying life in Milan and has endeared himself to team-mates

'No ceiling' for Milan or Tomori

In addition to his assured performances on the pitch, Tomori has also impressed fans with his command of Italian. It gives a sense he feels at home in Milan.

Friends are able to visit for a "mini holiday", enticed by cheap flights and the commanding power of Milan's stadium, the San Siro.

Last season's success led to a new contract, keeping Tomori at the club until 2027. He says he feels "very comfortable" in Italy and sees himself there "for the next few years" rather than heading back to the Premier League.

"Part of the reason why I signed a big contract was because I just feel very comfortable," he says. "When friends or family come, they enjoy themselves here and everyone feels welcomed into the city. There's a warmth about Milan.

"When I first came here, I really just wanted to learn Italian, to be able to communicate when I went out, and to learn the phrases on the pitch with my team-mates. I was doing lessons a lot when I first came in, but now I kind of just get by, by talking and listening.

"That's what helped me integrate into the culture and into the team."

Some might argue that the move to Milan has not helped with his integration into the England team. Tomori says he is "unsure" if more credit should have been given to his first title win.

But there is good news for Southgate. Tomori's quest for continued improvement means he is critical about his performances so far this season, and knows his best way to reach the World Cup is to continue to impress with Milan, starting on Wednesday.

The England manager will also benefit from a defender playing in a team that is still buoyed by last season's success.

Tomori added: "If I speak honestly I don't think I've started the season as I wanted to. The team has been playing well and I've been playing, but slowly I'm getting back to levels I know. Maybe there are moments in games where I know I could have done better, but it's up to me to correct it.

"With regards to England, it's always an honour to be called up and when I'm there I just try to give my best. If I don't play, I'm going to keep on trying to stay in the manager's mind whether that's in England training or whether that's here in Milan.

"There is history of Milan winning the Champions League and of course we would like to be part of that history. Last season no one really had us down to win the Scudetto but we knew the quality we had and we worked hard.

"If we approach every game in the Champions League like that, who knows where it can take us. For us as a team, I don't think we can really put a ceiling on ourselves."