Manchester United's most important player might be unavailable for the derby

Casemiro played against Uruguay during the international break, despite having sustained an injury in Brazil's previous game.

It seemed like a bizarre decision for Casemiro to play a full 90 minutes just four days after picking up a knock against Venezuela and it was presumed Erik ten Hag would be unhappy with Brazil for not taking the necessary precautions.

Ten Hag was asked about the injury at his press conference before the Premier League resumed. He was asked whether he was unhappy with the midfielder for playing and said: "You can’t - they are the rules."

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He continued: "And he’s played for his nation and he's playing for us and we all understand Casemiro is a solider and he is always available for every game, he will always give his best for his nation and Manchester United.

“He was injured in the first game and he came off but he played the second game, it was an important one. I’m sure that game didn’t help him but it’s a small injury and he’ll return next week and he will be healed and ready for our next game, I'm sure.”

Ten Hag probably wasn't so nonchalant until discovering the injury wasn't serious. The club have contended with an unprecedented injury crisis this season and having Casemiro on the sidelines for a period would have been another blow.

Casemiro's ankle injury was described as a 'small issue' and he returned to training two days after the Sheffield United game, which suggested he'd be available for selection for the Manchester derby at Old Trafford.

That was until Ten Hag threw his participation into doubt at his pre-match press conference on Friday afternoon when he confirmed Casemiro was