Pundit Sammy McIlroy said after the game that he thought Martial had suffered a hamstring injury, and so it has proved.
“I actually think that Martial had a knock. When he was coming over to the bench, he was feeling his hamstring. That’s why he came off. That could be an injury,” he said after the game.
The Athletic claim that the problem will keep him out of the game at Old Trafford but it is hoped he can return for the game after against Brentford.
Of course, the injury news will spark a conversation about whether Cristiano Ronaldo should be restored to the United starting lineup for the game.
Ronaldo has only played one game of pre-season – the 1-1 draw with Rayo Vallecano – and Erik ten Hag has said that the Portuguese’s decision to leave the stadium before that game had ended was ‘unacceptable‘.
Marcus Rashford could also play through the middle against the Seagulls, and that is how Ten Hag set his side up when Martial went off on Saturday.
Martial was one of the standout performers in pre-season but the fear was that he would be unable to carry it over when the serious action starts.
Of course, getting an injury is out of his control but it feels like a case of familiar frustrations for United fans, who have seen Martial struggle with fitness problems during his time at the club.
It is to be hoped that he is out for just one game, but even this absence could be enough to hand Ronaldo a route back into the side ahead of him.
If that does happen, it is up to Martial to work hard and get back into the team, and offer a more genuine alternative to Ronaldo than he did for much of last season.