Samu made his first-team debut on 14 January 2015, starting and playing the full 90 minutes in a 2–0 away win against Athletic Bilbao, in the season's Copa del Rey.[3] On 9 July 2017 he moved to another reserve team, after agreeing to a one-year loan deal with FC Barcelona B.[4]
On 21 June 2018, after featuring in only one match while on loan, Samu terminated his contract with Celta.[5]