Relvas was born in
Espinho,
Aveiro District. He played youth football with
S.C. Espinho and
C.D. Feirense, and made his senior debut in the lower leagues with
Gondomar S.C. and
F.C. Pedras Rubras. In the summer of 2020, Relvas moved straight to the
Primeira Liga after joining
Portimonense SC, being initially assigned to the under-23 team. After signing a professional contract on 29 July 2021, he made his competitive debut for the main squad on 1 August, featuring the entire 2–0 away loss against
Boavista F.C. in the
second round of the
Taça da Liga. His maiden league appearance took place one week later, when he also started the 1–0 win at
Vitória de Guimarães. Relvas scored his first goal in the Portuguese top division on 17 December 2023, but in a 5–2 defeat away to
Moreirense FC. On the last day of the January 2025
transfer window, he agreed to a three-and-a-half-year deal at Guimarães. On 28 June 2025, Relvas signed with
Super League Greece club
AEK Athens F.C. for
€3 million. He scored on his debut on 24 July, being decisive to a 1–0 victory over
Hapoel Be'er Sheva F.C. in the
second qualifying round of the
UEFA Conference League. His second came in the first leg of the competition's next stage, when he put his team ahead 2–0 in an eventual 2–2 draw at
Aris Limassol FC. ==Career statistics==