Roberto Mancini faces an anxious wait to discover the extent of Vincent Kompany's hip injury.
The Belgium defender has been a key component of Manchester City's defence this season but was forced off during the first half of Thursday night's 3-0 win over Aris Salonika.
With so many injuries decimating his squad at present, Mancini can ill afford to lose such an influential member of his first-choice starting line-up, especially with games coming every three days at present.
"We won't know what has happened until tomorrow (Friday) when we see what the situation is," said Mancini.
"We have a lot of injuries at the moment, so I hope it is not serious and he will be available for Sunday."