Born in Nova Iguaçu, Rio de Janeiro, Mathias played amateur football in his hometown before joining the youth sides of Ferroviária in 2021.

[2][3] Mathias made his senior – and Série A – debut on 11 August 2024, coming on as a late substitute for Rômulo in a 2–2 home draw against Athletico Paranaense.

[4] He scored his first professional goal on 5 October, netting a last-minute equalizer in an away draw against Corinthians for the same scoreline.

[6] In September 2022, Mathias was called up to the Brazil national under-17 team,[7] and played in the 2023 South American U-17 Championship.

He also was part of the squad which won the 2025 South American U-20 Championship, scoring a goal on the last match of the tournament.