Atlético Madrid said one of their supporters was hospitalized with serious injuries amid fan trouble ahead of the team's Copa del Rey second-leg semifinal against Athletic Club on Thursday.
Atletico president Enrique Cerezo told Movistar that some of the team's fans were allegedly attacked by Athletic supporters at a bar near San Mamés Stadium.
Spanish media said the arrival of Atletico's bus to the stadium was delayed several minutes. Images showed some fans lighting flares and throwing barriers against the stadium's doors before the match.
Police in riot gear were seen in the area, but authorities did not immediately confirmed the hospitalization of an Atletico fan.
Athletic won the first leg 1-0 in Madrid and went on to win the second leg 3-0 to reach the Copa del Rey final.
Information from The Associated Press was used in this story.
