Born in Ermua, Biscay, Arriaga emerged through Athletic Bilbao's youth system at Lezama, and was promoted to the first team for the 2002–03 season.

He made his debut in a friendly against farm team CD Basconia on 26 July 2002, coming on as a substitute for Julen Guerrero.

He first appeared in La Liga roughly one month later, playing the full 90 minutes against Real Sociedad in a local derby (4–2 away loss).

[1] Arriaga's importance would drastically diminish the following campaign, being only third or fourth-choice, and eventually had to resume his career in the second division, with SD Eibar and UD Las Palmas.

[2] He was loaned to Deportivo Alavés one league below in the 2010 winter transfer window after receiving very few opportunities,[3] and alternated between the second and third divisions of Spanish football the following years, with AD Ceuta, CD Guadalajara[4] and Gimnàstic de Tarragona.