"Niki Sule came in and I noticed that nobody went off," Freiburg defender Nico Schlotterbeck told
Sky after the game.
"Then the game started again, I first counted the players and then informed the referee. If I hadn't done that, I think he wouldn't have noticed."
Who was at fault for the incident?
Bayern boss Julian Nagelsmann blamed the electronic substitution board for the incident, and insisted that the away side made the effort to fix the mistake as soon as it was noticed.