Martínez made his professional debut on 7 January 2021, again replacing Franquesa in a 2–1 home win against CD Lugo, also for the national cup.[7] His Segunda División debut occurred on 28 March, as he started in a 2–1 home success over Albacete Balompié.
Martínez subsequently established himself as a starter, and scored his first professional goal on 9 May 2021 by netting the opener in a 4–1 away routing of UD Logroñés; aged 18 years and 14 days, he became the youngest goalscorer of the club's history.[8]
Career statistics
As of match played 20 December 2024
Appearances and goals by club, season and competition