Manchester City defender John Stones was absent from first-team training on Thursday ahead of their Premier League showdown with rivals Manchester United on Sunday.
The 28-year-old was recently involved with England on international duty and he started on the right side of a back three in the thrilling 3-3 draw with Germany on Monday.
However, Stones pulled up with a hamstring injury and was forced off in the 37th minute, with City teammate Kyle Walker brought on as his replacement.
Pep Guardiola has since reunited with his first-team squad following the international break, but not all of his senior stars were present in training on Thursday.
Sky Sports News have revealed some footage of the Citizens squad training at the City Football Academy, but there was no sign of Stones, raising further doubts over his availability for the Manchester derby.
Midfielder Kalvin Phillips was also missing as he is ruled out until at least November after undergoing shoulder surgery earlier this month.
City have been boosted by the return of centre-back Aymeric Laporte, however, who has been spotted training with his teammates and the Spaniard could be fit to feature in the matchday squad this weekend.
Laporte is yet to play for the Citizens this season after undergoing knee surgery over the summer and he also missed Spain's most recent international fixtures against Switzerland and Portugal.
Elsewhere, both Walker and Nathan Ake, who have previously been carrying injuries this term, were both seen training and the defensive duo will be hoping to force their way back into the first XI after watching on from the substitutes' bench in the 3-0 win over Wolverhampton Wanderers last time out.
Summer signings Erling Braut Haaland and Manuel Akanji, who scored for Norway and Switzerland respectively in the UEFA Nations League last week, also trained and they are both expected to retain their places in the starting lineup against United.
As for the Red Devils, Erik ten Hag could be without as many as six senior players due to injury this weekend, including centre-back Harry Maguire, who sustained a muscle injury in the closing stages of England's draw with Germany.
Anthony Martial remains sidelined with an Achilles injury, while Marcus Rashford (thigh), Donny Van de Beek, Aaron Wan-Bissaka (both knocks) and Martin Dubravka (muscle) are all doubtful and will be assessed ahead of kickoff.
After completing the double over Man United last season, Man City will be looking to secure their third successive victory against their rivals on Sunday and maintain their unbeaten start to the new season.
The Citizens currently sit second in the Premier League table, one point behind leaders Arsenal and five in front of the Red Devils in fifth who have played a game less. body check tags ::
