Boss Manuel Pellegrini does not know when Vincent Kompany will be fit to return for Manchester City following his latest calf injury.

The Belgian suffered a grade two tear against Sunderland on Boxing Day and his current lay-off is his 12th for a calf injury since the start of the title-winning 2011-12 campaign and his third this season.

Kompany was initially only expected to miss the first few weeks of the New Year but the Chilean manager hinted on Tuesday the central defender could be facing a lengthy spell out of action.

"It is difficult because Vincent is doing a lot of different things to try to understand and to find the reasons for so many injuries," said Pellegrini.

"At this moment it is difficult to tell you an update about that."

Pellegrini later added: "Vincent maybe not so soon, but for the last part of the season he could be fit."