Born in Tàrrega, Lleida, Catalonia, and a product of RCD Espanyol's youth system, Capdevila made his debut for its first team during the 1998-99 season, in a 2-2 La Liga draw at Athletic Bilbao, and joined Atlético Madrid the following year.
In the 2009-10 season, with no real competition for his position, Capdevila continued to figure prominently for Villarreal, only missing one league match - the defender added another five goals, but the club could not qualify for the UEFA Europa League this time, after finishing seventh.