Pep Guardiola has revealed Erling Haaland could miss Manchester City's FA Cup semi-final against Chelsea at Wembley on Saturday.
Haaland was substituted before the start of extra time in City's Champions League quarter-final second leg defeat against Real Madrid on Wednesday.
Guardiola said after the penalty shoot-out loss that the Norway striker asked to be withdrawn but did not give a reason why.
The City boss has now confirmed Haaland suffered an injury against Real and suggested it was not certain his leading scorer would recover in time for the FA Cup holders' clash with Chelsea.
"We will see. It was a tough game, a lot of action, high intensity for both sides," Guardiola told reporters on Friday.
"Erling felt something, a muscular issue. That's why he told me he could not continue.
"The doctor said he had a little bit of niggles, a little problem, we will see how his evolution is in the next hours."
While Guardiola sweats on Haaland's fitness, City midfielder Kevin De Bruyne should be involved against Chelsea after being taken off during extra time against Real due to fatigue.
Given City's hectic schedule, Guardiola conceded it is understandable that players are tired at this stage of the season.
"It's normal with the amount of games we are playing this season and the previous seasons and not much recovery, and extra time and high intensity," he said.
"We put a lot of pressure in our game and that's why the fatigue is there. They are human beings. They are not a machine. We are used to it."
The agonising shoot-out defeat by Real ended City's hopes of winning a Premier League, Champions League and FA Cup treble for a second consecutive season.
But they remain on course to repeat the domestic double and Guardiola is determined to ensure the Premier League leaders bounce back from their European frustration.
"We don't have another option. I don't want us to feel sorry for ourselves," he said.
"In football, you lose games. We performed at our best and we were not able to win. You have to accept it.
"We did everything. We know it, they know it, all the world know it, but it was not enough. When it's not enough, it's a bad night. So congratulations (to Real) and, tomorrow, FA Cup."
AFP