Alex is confident he can establish himself in Chelsea's star-studded team.
The former PSV Eindhoven defender said: "The level is the same at Chelsea. They have many players at the club who also play for their countries.
"I am sure all the players at Chelsea are the same quality in level as the Brazilian team."
Alex accepts his physical condition is not at the required level to claim a place in the Chelsea line-up, but he is determined to increase his fitness levels quickly.
The defender added: "I am aware of the situation but I've always had to fight for my place throughout my career.
"I want to get fit enough to be ready for when the manager calls for me.
"I expect to be fit in about two weeks from now. After three years waiting to get here, I am more motivated and happy to be here."