A product of CA Osasuna's youth ranks, he made his first-team – and La Liga – debut on 17 October 2004 in a 3–2 home win against Albacete Balompié, and finished his first season with 13 games and one goal,[1] scored in his first appearance.

[2] The following campaign, López was an undisputed starter as the Navarrese side achieved a first-ever qualification for the UEFA Champions League.

[3] As Osasuna were relegated to the UEFA Cup, López appeared 11 in matches in the team's semi-finals run, netting in 3–0 away defeats of Parma FC (twice)[4] and Bayer 04 Leverkusen.

[10] López netted six goals from 28 appearances in 2010–11 to match the highest total in his career, but he became a fringe player for the Lions after the arrival of Argentine Marcelo Bielsa as club manager.

[14] After leaving England at the age of 32, López spent three full seasons in his country's Segunda División, first with CD Lugo[15] and then SD Huesca.