Matheus debuted in the professional team on 25 March 2015, as a substitute, in a Rio de Janeiro State League match against Bangu. Flamengo won 2-1. Later in the same year he had his first Brazilian Série A appearance on 14 October 2015 against Figueirense. Flamengo lost 3-0 and Matheus played only seven minutes, again as substitute.[1]
On 5 January 2018 Flamengo announced the loan of Matheus Sávio to Estoril until the end of 2018.[3][4]
CSA (loan)
On 27 December 2018, Sávio joined CSA on a loan deal.[5]
Kashiwa Reysol
After a good performance playing on loan for Kashiwa Reysol Matheus signed, on 9 December 2019, his transfer from Flamengo to the Japanese club on a US$1.1 million. Flamengo received 50% of the transfer fee.[6]