Romelu Lukaku says he has matured as a player as he prepares for his Chelsea return.
Lukaku, 28, spent three years at the club between 2011 and 2014 before spells at Everton, Manchester United and Inter Milan.
The Blues re-signed him from Inter in a club-record £97.5m deal last week.
"Maturity has been important. I think I've learned much more about myself, setting higher standards," Lukaku said at his unveiling.
The Belgium international said he is fit to face Arsenal on Sunday having done a full pre-season with the Italian champions.
He added: "As a player, it's about becoming more complete. In Italy, the game is different, there are tighter spaces, it's more technical and tactical, which helped me a lot.
"I've done a full pre-season. For now, I just want to get to know my team-mates better.
"Then, at the end of the day, I'm available for the manager if he wants to play me."
Having taken the number nine shirt at Stamford Bridge after Tammy Abraham's departure for Roma, Lukaku says he is ready to fit into whatever system boss Thomas Tuchel has in mind.
"The English game is different but, for me, it's not something new. Whatever plan the coach has, I can adapt myself and help the team.
"I'm one of the players who likes to connect everybody and make everyone feel comfortable and give them confidence."
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