Schalke's mascot has escaped a punishment from the German Football Association (DFB) for showing the referee the red card after Saturday's draw with Borussia Dortmund, but the club have been warned they will be sanctioned if it happens again.
Referee Felix Zwayer ignored complaints from Schalke players who felt they should have been given a penalty when the ball made contact with Marc Bartra's hand.
As the protests wore on, Schalke coach Markus Weinzierl was sent to the stands and Zwayer misplaced his card.
The Gelsenkirchen side's mascot, Erwin, picked it up and brandished it at the referee, who noted the incident down in his notebook.
It prompted concerns the mascot could face some punishment, but the DFB has let the Bundesliga side off with a warning.
"The club was informed that in the event of repetition, it would have to face a sanction," a disciplinary committee statement read.
Although Zwayer was not amused by the action of the mascot, he was more relaxed about it later but admitted: "It was not that funny at the time."