Benjamin Mendy, Kevin De Bruyne and Fernandinho remain side-lined, although Ferna would have been suspended for the clash.
Nicolas Otamendi trained, but is suspended for this game after being sent off in the first leg in Germany.
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Cameron Humphreys and Eric Garcia both took part in the mid-afternoon CFA session, under the watchful eyes of the media.
Aymeric Laporte, who returned as an unused sub against Watford on Saturday, could feature against Schalke.
Those who trained:
Aro Muric
Daniel Grimshaw
Phil Foden
Danilo
Riyad Mahrez
Leroy Sane
Fabian Delph
David Silva
John Stones
Nicolas Otamendi
Eliaquim Mangala
Cameron Humphreys
Raheem Sterling
Ilkay Gundogan
Eric Garcia