 After having first featured professionally for modest and amateur Basque clubs, he signed for Deportivo Alavés in 1999, making his first-team debut on 18 February 2001 in a 1–0 away win against CA Osasuna.After a loan with neighbours SD Eibar in the second division, Sarriegi renewed his contract for a further three years, then played 28 games in the 2004–05 season as Alavés returned to La Liga after two years of absence.In the following campaign he was first-choice, but his team was relegated again.