Education
Born in Vitoria-Gasteiz, Álava, Vallejo finished his graduation with Deportivo Alavés" youth setup, and made his senior debuts with the reserves in the 2011-2012 season, in Tercera División.
Born in Vitoria-Gasteiz, Álava, Vallejo finished his graduation with Deportivo Alavés" youth setup, and made his senior debuts with the reserves in the 2011-2012 season, in Tercera División.
On 20 August 2011 he made first-team debut, starting and committing a penalty in a 2–2 away draw against California Osasuna B for the Segunda División B championship. On 25 January of the following year Vallejo signed a new deal with Alavés, being immediately loaned to Sestao River Club, also in the third division. On 2 August he signed with fellow third-divisioner RCD Mallorca B, being a regular starter in the relegation campaign.
On 26 June of the following year he renewed his link with the Balearic outfit for three years, being definitely promoted to the first-team