Bayern Munich briefly played with 12 players on the pitch towards the end of their 4-1 thrashing of Freiburg on Saturday.
The Bavarians were already coasting two goals ahead when the incredible mix-up occurred in the final minutes of the Bundesliga clash. The situation caused a significant delay as the two sides met with the officiating staff to sort out the issue.
Bayern played for a number of seconds with an additional player on the pitch before the error was noticed and corrected.
That numerical irregularity was eventually resolved, and Bayern would go on to nine points clear at the top of the table, while Freiburg remains three points back of the final Champions League place.
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What happened in Bayern vs. Freiburg?
Just over 80 minutes of Saturday's game had been played when a late Bayern substitution led to chaos on the pitch.
With Bayern leadingn the match 3-1, Niklas Sule was sent into the action to replace Corentin Tolisso, who was forced off through illness having himself come on as a substitute. Sule, however, came on before Kingsley Coman, who was subbed off at the same time for Marcel Sabitzer, had been removed from the field, leaving Bayern momentarily with 11 outfield players.
A handful of seconds were played before the game was stopped and Coman was withdrawn as intended to restore the appropriate number of footballers. Sabitzer would later add a fourth goal for the visitors before the final whistle.
"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."
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What caused the Bayern substitution mistake?
According to Bayern coach Julian Nagelsmann, a mix-up with the electronic substitution boards was to blame, and as soon as the mistake was noted the away side moved to fix it.
Instead of Coman's No.11, the 29 came up, a number that does not belong to any of the Bayern squad.
"It was a vague situation. Coco [Tolisso] had stomach problems and ran into the dressing room. Coman didn't know he had to go off too and stayed on the pitch for eight to nine seconds. It was nothing game changing," he told reporters.
While it was only a short period of time, Freiburg were left furious by the confusion.
"That was an extremely bizarre scene that I have never experienced before. Does that have an impact? I cannot judge now," sporting director Jochen Saier fired.
"The referee evaluated it for a long time, then let play continue. Will Freiburg protest? We have to calm down now and think about it."
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Could Bayern be punished for the mistake?
According to Bundesliga rules, a team fielding an inappropriate amount of players could be forced to forfeit the match.
"If a player is not entitled to play or to field a game, the team that culpably fielded this player loses the game 0-2 and the opponent wins 2-0, unless the match has not been restarted by the referee after the player who is ineligible to play has been fielded," per the DFB's rules.
Freiburg so far have not indicated whether they will seek action against Bayern over the matter, but given that victory would have seen them keep on pace with fourth-place RB Leipzig in the race for the Champions League, the matter is likely to rumble on over the coming days.
"It's a violation of the rules," said former Bayern player Dietmar Hamann while covering the game for Sky Sport Germany. "If one goes onto the field, another has to go down. It doesn't matter whether they play 20 seconds, twelve or five minutes.
"There is no question in my mind that it must be punished."
However, if indeed the mistake was caused by the incorrect number being shown on the electronic board, that would mean the blame lies with the fourth official, a member of the officiating staff, and Bayern would almost certainly not be punished for the incident. It would be harsh to punish the team when Coman would not have been expected to know he is meant to be withdrawn, and the match referee did not notice the error before restarting the match.
