Gio Reyna was pulled from Borussia Dortmund's 4-0 win over Schalke during warm-ups due to an injury.
Dortmund manager Lucian Favre said that he expected players to get injured because of the long layoff.
"A lot of teams will have a few players who will be injured. We started very late with the 10 against 10 games, tackling and so on. I hope Reyna has nothing. It won't be long for [Axel] Witsel and [Emre] Can, [Dan-Axel] Zagadou won't play again this season," said Favre.
Favre added that it was difficult to judge the quality of his side's win due to the lack of supporters.
"There wasn't any noise, you shoot at the goal, make a top pass, a goal - and nothing happens. That's very, very strange. We really miss our fans.
"It was a completely different game than usual. It's hard to judge how good the game was. I had the feeling that it wasn't as committed as planned. The players were very focused on their task."