[5] Martí made his single-seater debut in January 2021, driving for Xcel Motorsport in the Formula 4 UAE Championship.

[10] For the main season, he competed in Spanish F4 with Campos Racing, as the Valencian team made its debut in the championship.

[20] During 2023 pre-season, Martí returned to the 2023 Formula Regional Middle East Championship with Pinnacle Van Amersfoort Racing.

[23][24] After testing for the team in 2021 post-season, Martí made the step up to the FIA Formula 3 Championship in 2022 with Campos Racing.

[31] Martí continued with Campos Racing for the 2023 Formula 3 season alongside Christian Mansell and Hugh Barter.

[32] He started the season in the best fashion during the sprint race as from second, he overcame Franco Colapinto for the lead before proceeding to take his first F3 victory.

[41][42] Starting on reverse pole for Austria, Martí controlled the majority of the sprint race, but a late safety car led to him struggling after that; he rapidly dropped to sixth during the last three laps.

[45] Despite being a pit stop mid-race to fit wet tyres, in which in proved to be the eventual wrong choice, Martí managed to fend off a faster Alex García for tenth.

[51] In the feature race, he made a wrong gamble on slick tyres on a damp track, as he slipped to ninth at the flag.

[56] Martí graduated to Formula 2 for his 2024 campaign, continuing his relationship with Campos Racing alongside fellow Red Bull junior Isack Hadjar.

[59][60] Qualifying 11th again in Jeddah, but in the sprint race he manage to progress to seventh place having forced an error on Kush Maini on the final lap.

[64] After qualifying eighth in Austria, he vaulted to second early on in the sprint race, and despite pressure on leader Bearman, Martí did take his first podium since Bahrain.

[70] He was involved in a scary crash during the Baku feature race after he piled into a stalled Kush Maini, causing Martí's car to flip upside down.

[74] Martí continued with Campos Racing for the 2025 season, alongside his fellow Red Bull junior Arvid Lindblad.

[75] In September 2022, Martí was announced to join two-time Formula One champion Fernando Alonso's management team.