He currently plays for Etoile Carouge, wearing the number 20 shirt. At the international level, he represents Switzerland U20. He plays primarily as a Midfield. His preferred foot is Left. His current market value is estimated at 200K €.

His most recent move was a Loan from Etoile Carouge to Luzern on 2026-06-29.

Across 16 appearances in the Switzerland Challenge League 2025-2026, Mattia walker registered 0 goals and 0 assists, while completing 0 key passes out of 0 total passes with a passing accuracy of -.