Atletico Madrid's Diego Costa sits in the pitch after injuring in his right leg during their Champions League quarterfinal first leg soccer match against Barcelona at Camp Nou stadium in Barcelona, April 1, 2014. [Photo/Agencies]

BARCELONA - Atletico Madrid's chances of domestic and European success suffered a blow when their top scorer Diego Costa picked up a hamstring injury in Tuesday's Champions League quarterfinal, first leg at Barcelona.

Costa, who has seven goals in five matches in Europe's elite club competition this season and 25 in 30 La Liga outings, pulled up clutching the back of his thigh and was forced off after half an hour with the score at 0-0 at the Nou Camp.

"Diego Costa has a muscle injury at the back of his right thigh," Atletico said in a statement on their official Twitter feed. They did not say how long the 25-year-old Spain international might be sidelined.

Atletico are a point clear of Barca at the top of La Liga with seven matches left and host the Catalan club in their Champions League quarterfinal, second leg match on April 9.