Pep Guardiola has suffered a huge injury blow with Sergio Aguero set for a spell on the sidelines.
The club’s record goalscorer limped off in the 77th minute of Manchester City’s 2-1 win over Chelsea with what looked like a groin injury.
He will now definitely miss Tuesday’s home Champions League clash against Shakhtar Donetsk and could be sidelined for a number of weeks.
City boss Guardiola said: “It is a muscle injury but it does not look good.
“I don’t know how long he will be out the doctor will look at it.”
David Silva and Rodrigo also went off injured during the game but neither was serious.
Guardiola said: “It was just tiredness and cramp.”
Guardiola won yesterday despite enjoying the lowest amount of possession in his 381 game top flight managerial career at 46.74 per cent.
As boss of Barcelona, Bayern Munich and Manchester City it is usually the opponent playing without the ball
But yesterday it was City who had to suffer spells like that against an impressive Chelsea side.
Guardiola joked: “Always there is one thing in your life that hasn’t happened.
“It is another record I have. I have won a game without the most possession.”
He did that as his City side came back from a N’Golo Kante 21st minute opener with goals from Kevin De Bruyne in the 29th and Riyad Mahrez eight minutes later.
Guardiola was delighted with the win against a very impressive Chelsea side and he was full of praise for their manager Frank Lampard.
He said: “Frank is a courageous manager.
“I try to judge a manager by the courage he has to play and Chelsea have a fantastic team.
“We beat an incredibly top side.”
Lampard was pleased with his team’s performance but said it is the finer details that set Manchester City and Liverpool apart.
Lampard said: “I wanted to come here and be brave and compete and be brave on and off the ball and you saw that from us in the first half.
“Throughout the game you saw a lot of positives but we lost the game.
“The finer details in both boxes are what decided the game.
“Teams like City and Liverpool have been getting results for a long time because they work hard and the finer details they get right.”