Ronaldinho marked his return to the Brazilian top-flight by helping set up Fluminense's goal in a 1-0 win over his former club, Gremio.
The former Brazil international and two-time FIFA World Player of the Year was making his first appearance since his departure from Liga MX outfit Queretaro.
Ronaldinho drifted a long pass to Wellington Paulista, who nodded down to Marcos Junior to score the 77th-minute winner in Rio de Janeiro.
Gremio had been reduced to 10 men early in the second half when Walace saw red.
Fluminense are third in the Brazilian Serie A, while fittingly for Ronaldinho, the clash was against the club he grew up at in Gremio.
The 97-time Brazil international has enjoyed spells at Flamengo, Atletico Mineiro, Queretaro and Fluminense since his decorated career in Europe came to an end in 2011.
Ronaldinho is contracted at Fluminense until the end of 2016, when he will be 36.
Fluminense's next outing is a trip to Avai on August 8.
