Arjen Robben and Jerome Boateng were both taken off in the first half against Real Madrid on Wednesday due to a muscle injuries.
The Dutch winger pulled up just five minutes into the Champions League semi-final first leg at the Allianz Arena and after attempting to walk the injury off, he had to be removed from the game.
Thiago Alcantara entered the match in Robben's place, with Thomas Muller moving out wide from his central position.
Just 25 minutes later, Boateng pulled up with what appeared to be a hamstring injury after stretching out to reach the ball and overextending himself.
Niklas Sule was quickly inserted into the match in place of his fellow Germany international.
Robben has struggled with injuries for much of his career but has been mostly healthy in 2017-18, scoring seven goals and adding 12 assists in all competitions.
Boateng has also dealt with injury problems during his time in Munich, and has additionally found himself on the bench sporadically this season.
Both players will now be a doubt for the second leg of the semi-final tie, which takes place in just six days' time in Madrid.
Robben's contract expires at the end of the season, but Bayern sporting director Hasan Salihamidzic recently hinted he would be given a new deal along with fellow wideman Franck Ribery.
