Samir Nasri admits Manchester City let themselves down last season.
Nasri concedes that City underachieved badly last term, as they ended the season empty-handed, but is confident they will bounce back stronger in 2013/14.
He said: "It was certainly a very disappointing season and losing our title of English champions was a failure that was difficult for the whole squad to swallow.
"We didn't manage to win a single trophy, and that's disappointing for a club with the standing of Manchester City. We had a very testing year but we'll learn from our mistakes to have an excellent season next year."