[3] Born in Galdakao, Basque Country, Antón's first major achievement after turning professional in 2005, was winning the sixteenth stage of the 2006 Vuelta a España, between Almería and the Calar Alto Observatory.

Later in the same month, Antõn won the second stage in the UCI ProTour race Tour de Suisse.

In September at the Vuelta a España, Antón was in the best form of his career and held the pace of the likes of Alberto Contador and Alejandro Valverde up the mountains.

He won the mountainous first stage of the Vuelta a Asturias with fourteen seconds of an advantage over former Euskaltel teammate Amets Txurruka of Caja Rural–Seguros RGA.

A few months later, his career was honoured by local football club Athletic Bilbao at their stadium prior to a derby match against Eibar.