Leeds United midfielder Lee Bowyer was banned for six matches by UEFA on Wednesday for stamping on an opponent's head during a UEFA Cup match against Malaga last month.
European soccer's ruling body announced the heavy punishment after finding Bowyer guilty of "an act of serious assault, stamping on an opponent's head" in the third-round match at Elland Road on December 12.
Bowyer, who is set to complete a move to West Ham United this week, has until 2300 GMT on Saturday to lodge an appeal against the suspension, which applies only to European club competitions.
Television replays showed Bowyer treading on Malaga defender Gerardo in the 16th minute of the second-leg clash, which Malaga won 2-1 to eliminate Leeds by the
Leeds manager Terry Venables later said the 26-year-old had admitted standing on Gerardo.
UEFA then charged Bowyer with "unsporting behaviour" and, after examining video evidence, announced the stiff punishment in a statement on Wednesday.
Although UEFA said the ban would "take effect immediately", Bowyer will not actually serve the suspension until his club plays again in European club competition.
Leeds are out of the UEFA Cup and West Ham, Bowyer's prospective new club, are not playing in European competition this season.
However, UEFA says the ban, which is the equivalent of an entire Champions League group phase, has a shelf-life of six years.