Manchester United earned a draw with Aston Villa at the weekend and that point may have come at a cost.
The Europa League and Premier League schedule is a tough one for clubs to handle, with matches on Thursday and Sundays.
Rotation is required for squads to cope, and the one position where Manchester United are unable to rotate is at full-back.
United only have two fit full-backs, and now that number is down to one.
Noussair Mazraoui latest
Manchester United had to make two substitutions at half-time against Aston Villa, with Harry Maguire and Noussair Mazraoui taken off at the interval.
Harry Maguire was spotted in a protective boot after the game, an ominous sign.
And now a worrying update has emerged over Noussair Mazraoui, who was due to link up with the Morocco squad.
As relayed via Fabrizio Romano, Noussair Mazraoui has now withdrawn from the Morocco squad, with a replacement called up.
Morocco are due to play two African Nations Cup qualifiers over the break, and will have to do without the Manchester United defender.
Noussair Mazraoui injured
Noussair Mazraoui had a patchy injury record at Bayern Munich, but had made a positive start at Manchester United.
The problem is, he has not had a break at United, due to the lack of rotation options at the position.
He was making his 10th start for Manchester United against Aston Villa, and is now out with an injury.
The extent of the problem is yet to be determined, yet it’s enough to keep him sidelined during the international break.
Kobbie Mainoo injured too
Kobbie Mainoo has now also pulled out of the England squad with an injury, the FA have confirmed.
The FA have announced Mainoo is one of three players to pull out, citing an injury sustained over the weekend.
The news follows Alejandro Garnacho pulling out of the Argentina squad too, having been battling an injury over the past week.
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