Updated

Manchester City right-back Micah Richards has been ruled out of action for four months after undergoing surgery to fix a knee injury sustained in the club's defeat of Swansea City on Saturday.

It had been thought that Richards would be sidelined for just six to eight weeks, but he revealed after the operation that he is likely to be out twice as long.

"The positive thing is that the injury has been repaired so the knee will be as good as new," Richards told the club's official website. "I have a brace on it and I am using crutches. I can't do anything at all for the next four to six weeks and I am probably looking at 12-16 weeks before I am back in action."

Manager Roberto Mancini now faces a selection dilemma ahead of the club's Premier League match against West Ham on Saturday. Pablo Zabaleta and Maicon missed City's tilt with Swansea with injuries, though Zabaleta could be fit in time for the trip to Upton Park.