* Costa suffers hamstring injury
* Playmaker Arda bruises a hip (Adds Atletico injury update)
MADRID, May 17 (Reuters) - Atletico Madrid suffered a double blow that may affect their chances in next weekend's Champions League final when top scorer Diego Costa and playmaker Arda Turan limped out of Saturday's La Liga showdown at Barcelona.
Costa was forced off in the 16th minute of the clash at the Nou Camp with a hamstring injury in his right leg and Arda followed him just over five minutes later after bruising a hip following a collision with Cesc Fabregas.
Atletico confirmed the injuries on their Twitter feed and they potentially put the pair's participation in next Saturday's European showpiece against Real Madrid in Lisbon in jeopardy.
Costa is in the preliminary Spain squad for the World Cup finals and is expected to be included in the holders' final list for the tournament in Brazil starting next month.
Atletico need a point to secure their first La Liga title in 18 years, while only a win will do for Barca, who are chasing a fifth title in six years. (Reporting by Iain Rogers, editing by Justin Palmer)