Manchester City manager Manuel Pellegrini has admitted that the latest injury suffered by Vincent Kompany is not good news for his side.

The Citizens have struggled without their captain so far this season and saw his return from a calf injury last just nine minutes during this afternoon's 4-1 victory over Sunderland at the Etihad Stadium.

Pellegrini insists that the Belgian was ready to make his comeback, and admits that it is "difficult to understand" why he suffered a recurrence of the calf injury.

"Vincent is not the best news. He was ready to return. I did not want him to play the whole game because we have to play so many games, but he worked the whole week with normality," Pellegrini told reporters.

"It is really difficult to understand what happened. We will see tomorrow with the doctor's report but it is the same injury, the same calf."

Meanwhile, Kompany has vowed to overcome his latest injury setback.