Manchester City striker Erling Haaland is a doubt for his side's FA Cup semi-final against Chelsea on Saturday.
Haaland was substituted late on during Wednesday's Champions League quarter-final defeat on penalties by Real Madrid.
City boss Pep Guardiola said after the game that the 23-year-old had asked to be taken off.
"We will see," said the Spaniard on Haaland's availability to face fellow Premier League side Chelsea at Wembley.
"It was a tough game, a lot of action, high intensity for both sides. 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."
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City midfielder Kevin de Bruyne also asked to be taken off against Real but should be fit to play.
"Kevin felt exhausted, so tired, after five months out injured [earlier on in the season], so that's normal," added Guardiola, who has defended selling forward Cole Palmer to Chelsea in the summer.
"It's normal with the amount of games we are playing this season ... They are human beings. They are not a machine. We are used to it."
City will be aiming to bounce back from their Champions League exit when they face Chelsea.
"We don't have another option," said Guardiola, whose side are top of the Premier League with six games to go. "I don't want us to feel sorry for ourselves.
"In football, you lose games. We performed at our best and we were not able to win. You have to accept it."
Chelsea manager Mauricio Pochettino, whose side lost the Carabao Cup final to Liverpool earlier this season, could have midfielder Enzo Fernandez and winger Raheem Sterling back after injury and illness respectively.
Pochettino hopes City's exertions against Real will work in his side's favour.
The Blues have drawn 4-4 and 1-1 with City in the league this season.
"We know very well, when you play 120 minutes in the Champions League, the effort is massive. And the emotional thing, it's always not easy to recover after you lose," said Pochettino.
"Of course it will be tough for them, like it will be for us. But we need to remember they have an unbelievable squad."
Source: BBC
BDST: 1257 HRS, APR 20, 204
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