The 30-year-old picked up the injury during City's defeat to Real Madrid on Wednesday night
Manchester City are still waiting to find out the extent of the injury suffered by Vincent Kompany during Wednesday night's Champions League's exit to Real Madrid.
The Belgian international was withdrawn after less than 10 minutes with what appeared to be a groin injury and could cast doubt over his involvement in this summer's European Championships in France.
"We don't have yet the medical examinations so we don't know exactly in this moment. He is with the doctor making some exams. Probably on Monday we will know" said Manuel Pellegrini.
"Every time he was in the starting team it was because he was fully fit to play - you can be absolutely sure (of that). The other reasons he couldn't play the full game is more of a medical answer.
"It is an issue for the future that I don't feel I must answer. You must talk with the doctor and the player and the people who will be in charge of Manchester City next season. It is not an answer I can give. It is a medical answer."
This is the 33rd injury of his City career.