Willy Caballero has told Manchester City boss Manuel Pellegrini that he can depend on him if first-choice goalkeeper Joe Hart is ruled out for a while.
Hart, 28, suffered a hamstring injury in Wednesday's 1-0 Champions League defeat to Juventus and is expected to miss Saturday's Premier League visit of Southampton.
His understudy Caballero has not been seen since making a series of costly errors in City's 4-1 defeat at Tottenham Hotspur earlier in the season, but the 34-year-old feels ready to atone.
"Of course it is not good that Joe had to come off against Juventus late in the game, but I have to be prepared – that is the life of a substitute goalkeeper," he is quoted as saying by The Mirror.
"If I am needed, I will be ready, whenever that might be - but of course we hope that Joe recovers, he is a goalkeeper of the very highest level, and he is playing very, very well.
"What happened to me [at Spurs], I have not had the chance to avenge that error, and the whole world still thinks about it. But what is important is to be calm and work every day and wait."
Pellegrini's side sit third in the league table, two points off high-flying Leicester City at the summit.