Marcel Mendes-Dudziński was born in Szczecin on 14 May 2005 to a Polish mother and a Brazilian father, and holds both Polish and Brazilian nationality. He was formed at Pogoń Szczecin before Benfica signed him in August 2021 for the under-19 squad.

A left-footed goalkeeper standing 1.93 m, he wore the number 50 and was promoted to the under-23 and Benfica B squads for 2023/24. Benfica extended his contract to 2028 in October 2023, but he made no official senior appearance for the club and never featured for the first team.

He returned to Poland in July 2024 with Legia Warszawa, spent the first half of 2026 on loan at Świt Szczecin, and joined Piast Gliwice in July 2026. He has represented Poland at under-19 level.