Midfielder Bastian Schweinsteiger's knee injury has made him doubtful for Manchester United's English Premier League (EPL) match away against Newcastle United on Tuesday night.
The Germany captain was injured towards the end of the 1-0 Emirates FA Cup win over Sheffield United on Saturday and, initially, it looked as though he would be leaving the field on a stretcher.
Instead, he gamely battled on rather than leave the Reds -- who had already used all three substitutes by that point -- down to 10 men and, thankfully, Wayne Rooney kept his nerve to fire home an injury-time penalty.
With another fixture on the horizon, Morgan Schneiderlin, Michael Carrick and Ashley Young were rested after their recent exertions, while coach Louis van Gaal felt Andreas Pereira showed his quality with a cameo appearance off the bench.
"It will be difficult of course (for Schweinsteiger to face Newcastle)," van Gaal told the club's website manutd.com.
"I don't know yet but I think he has a knee problem. Everyone thinks he has an ankle problem but I think it's more the knee than the ankle. We'll have to wait and see."
Van Gaal felt that midfielder Schneiderlin needed rest after the France international played every game during festive fixtures.
"Schneiderlin is not injured but he's in the red zone and had an overload. In the Christmas period, he played every game and we have to take care of that," van Gaal said.
"I don't take risks and, because of that, we have a very young bench. I trust these players also because Pereira is coming in and was a very good substitute, I think," the Dutchman added.
"With our injuries and players in the red zone, we have to take care of it. I think we have done it well."