 He met the club's eligibility standards having been raised in the Basque town of Iurreta and through his parents, both of whom hailed from the region.After progressing through the ranks – alongside Fernando Llorente– including CD Basconia (the farm team) and Bilbao Athletic (the reserves), he made his first-team debut in 2005–06, becoming an undisputed first-choice in the subsequent La Liga seasons.Amorebieta played in a total of 47 official matches in 2009–10, helping Athletic reach the round-of-32 in the campaign's UEFA Europa League as well as an eighth-place finish in the league; he collected 18 yellow cards in the process, being sent off twice.