Antonio Rudiger is a doubt for both legs of Real Madrid's Champions League play-off against Manchester City later this month after sustaining a thigh injury in his side's 1-0 defeat to Espanyol over the weekend.

Former Chelsea defender Rudiger, 31, lasted just 15 minutes in Saturday's clash at the RCDE Stadium before he was replaced by Raul Asencio after pulling up with injury.

On Sunday, Real Madrid confirmed that the club's medical team had assessed Rudiger and subsequently diagnosed him with a thigh injury which will be monitored in the weeks ahead.

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Spanish publication COPE reports that the Germany international is set to be sidelined for three weeks, which would rule him out of Madrid's crucial two-legged Champions League tie against City.

City welcome the reigning European champions to the Etihad in the first leg on February 11, with Pep Guardiola's side making the trip to the Spanish capital eight days later.

Despite suffering away defeats to Sporting CP, Juventus and Paris Saint-Germain, City qualified for the play-off round of the Champions League with a 3-1 win over Club Brugge last Wednesday.

And asked for his assessment of the competition after the match, Guardiola, though, refused to rule out City winning the Champions League for a second time this season.

"Right now, no. I'm so pragmatic, the reality is the reality," said the former Barcelona and Bayern Munich manager. "These teams [Bayern and Real] have more experience than us, if we had to play tomorrow it would be difficult, but in two weeks I don't know the position we will be. We are going to prepare well and try it, we'll see what happens."