Adrián San Miguel del Castillo started his career at Real Betis, first with the club’s minor teams, until making his first-team debut in 2012; he also had loan spells with Alcalá and Utrera during this time.

Adrián first signed for Liverpool on a free transfer on the 5th of August, 2019. He extended his contract with Liverpool until the conclusion of the 2023-24 season on June 30, 2023.