The Argentine has made it clear to England's No.1 that he has not joined Manchester City from Malaga to sit on the benchWilly Caballero has warned Joe Hart he has not come to Manchester City just to sit on the bench.
The Argentine goalkeeper, 32, completed a move to the Etihad Stadium from Malaga earlier this month.
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"I know the situation now but I will fight to play. The decision will be down to the coach, the boss. I have trained well and I will fight," said Caballero.
"I know my position, but I want to try hard to fight for this position. Joe is a fantastic goalkeeper, but I've come to play - I want to try and take my opportunity.
"It will be difficult, yes, but City are a big club and it's a big opportunity. I want to try in every way I can to play."
Caballero acknowledged that Pellegrini was a major factor in his decision to join City.
"It was a crucial part of me coming to City knowing him from before and having played for him. He was a very important figure in me coming to Manchester City," added the experienced stopper.
"I had no doubt about the move. I think it was necessary for my career, for my life and for my family. It's fantastic for me.
"He hasn't given me any promises. No, I only know that he wanted me. I came here for the best opportunity for my career.
"I don't know if I play in the cup or other tournaments, I don't know anything. But of course I am confident.
"Goalkeepers are a different type of player and I believe in myself."