Gabriel Jesus and John Stones missed the open section of Manchester City's Tuesday training session ahead of the Premier League side's trip to Schalke in the Champions League.
Striker Jesus and centre-back Stones played the entirety of Saturday's 4-1 win at Newport County in the FA Cup but are reportedly suffering from hamstring and groin complaints respectively.
Stones featured in every match as City topped their group, with Jesus netting a hat-trick in the 6-0 win over Shakhtar Donetsk.
There was better news for Pep Guardiola ahead of Wednesday's match in Gelsenkirchen as club captain Vincent Kompany and left-back Benjamin Mendy trained for the second successive day following their latest spells on the sidelines.
Kompany has not featured since his troublesome calves flared up again during last month's 2-1 win over Liverpool, while Mendy suffered swelling following his return from knee surgery against Burton Albion in the semi-finals of the EFL Cup.
City face Chelsea in the final of the latter competition at Wembley on Sunday.