Question:  The 2008–09 Copa del Rey final was held at a football stadium which as a seating capacity of what?
Sentence (from "2009 Supercopa de España"): It was contested by Athletic Bilbao, the 2008–09 Copa del Rey runners-up, and Barcelona, the 2008–09 Primera División and 2008–09 Copa del Rey winners.
Relevant evidence: No