 Marquinhos joined Corinthians at the age of eight in 2002. After winning the state junior cup, he was first included in a senior matchday squad on 29 January 2012, remaining an unused substitute in their 1 – 0 home win over Clube Atlético Linense in the Campeonato Paulista. He made his professional debut in the competition on 18 February, playing the full 90 minutes of a victory by the same score at Associação Desportiva São Caetano. He made eight appearances across the season, as the Timão topped the table in the regular season but were defeated by Associação Atlética Ponte Preta in the play-offs quarter-finals.
