Schalke striker Klaas-Jan Huntelaar has been banned for six games after his red card against Hanover 96 on Saturday.
The 31-year-old Dutch international was shown a straight red card for a reckless tackle from behind on Manuel Schmiedebach during his side's 1-0 win.
Schalke say they will appeal the German Football Association's decision.
"We believe this was not a matter of violent conduct," club board member Horst Heldt told their website. "That's not something Klaas-Jan would do."
He added: "Surely, the red card was justified, but we consider a six-match-ban too high a punishment. This is why we are appealing."
Huntelaar said: "I was completely perplexed with the red card because that challenge did not really look that hard and because I am not a hard player."
"In my entire time in the Bundesliga I have only once been sent off and that with a double booking."
Huntelaar has played in 17 of his side's 18 league games this season, scoring seven goals.
Schalke, who face Real Madrid in the Champions League last 16 this month, are fourth in the Bundesliga and visit leaders Bayern Munich on Tuesday.