Born in Murcia to a Lithuanian mother,[2] Valera joined Atlético Madrid's youth setup in 2018, from Villarreal CF.
[3] Promoted to the reserves for the 2019–20 season, he made his senior debut on 24 August 2019, coming on as second-half substitute in a 2–1 Segunda División B away win against Marino de Luanco.
[5] He made his first team – and La Liga – debut the following 4 January, replacing João Félix late into a 2–1 home success over Levante UD.
[6] On 1 February 2021, Valera renewed his contract until 2026 and moved to Segunda División side CD Tenerife on loan for the remainder of the season.
[7] On 11 August, he moved to fellow second division side Real Sociedad B on a one-year loan deal.