Manchester City are concerned that Sergio Aguero could be missing for up to six weeks, according to a report.
The striker scored in the 6-3 win against Arsenal, but had to be replaced after getting a knock.
He then left the stadium on crutches with his right leg in a protective casing.
If a scan shows that Aguero has suffered a grade two or grade three muscle tear, then he could be out for six weeks, claims The Mirror.
Aguero has scored 12 Premier League goals this season.