Kingsley Coman has undergone minor heart surgery, according to Bayern Munich coach Julian Nagelsmann.
The 25-year-old has already made four appearances for the Bundesliga giants this season, including an eight-minute cameo in Tuesday's Champions League victory over Barcelona.
After undergoing a cardiac operation, the France international is expected to be out for a while, but he could return to first-team training in the coming weeks.
"King' had an operation yesterday, he had a minor heart rhythm disturbance. I'll explain that with my little medical expertise," Nagelsmann told reporters.
"There are two strands that activate the sinus node. One of them was cut off so that there would be no additional blow. Sometimes he had less air for a short time and was less productive. That's why we did a long-term ECG (electrocardiogram) and found something that could be fixed quickly.
"He'll start cardio on Tuesday. It won't take much longer than a week and a half or two before he's back in team training."
Coman, who has been linked with a move away from Bayern Munich, could be available for Bayern's Bundesliga match against Eintracht Frankfurt in early October.