Manuel Pellegrini has revealed that Vincent Kompany suffered a recurrence of his previous calf injury in the goalless draw against Dynamo Kiev.
The Citizens' skipper limped off less than 10 minutes into the second leg of the Champions League last-16 clash after pulling up innocuously.
Supporters' initial fears have now been realised, as manager Pellegrini confirmed post-match that the Belgium international's latest injury setback is once more linked to his troublesome calf.
Kompany has already missed large chunks of this season as a result of the issue, and will now likely miss a key part of City's end-of-season run-in - though the extent of the injury has yet to have been confirmed.
Speaking to BT Sport after the match, Pellegrini said: "Unfortunately for Vincent, he has a calf problem again in his muscle so we will see how it is tomorrow.
"It is difficult for Kompany because he came back very well, he played six games in-a-row but unfortunately for him he couldn't continue."
To make matters worse for the Premier League outfit, Nicolas Otamendi was also withdrawn in the first half of a stalemate that helped seal progression into the last eight of the competition.