Gremio’s Brazilian Serie A football title hopes suffered a blow here when they lost 0-1 to Vasco da Gama.
Teenage midfielder Mateus Pet scored a first-half winner, meeting Ramon’s cross with a sliding volley at the far post on Saturday, reports Xinhua news agency.
Gremio remained second in the 20-team standings with 43 points, seven points behind Corinthians, who were due to visit rivals Santos on Sunday.
In Belo Horizonte, reigning champions Palmeiras drew 1-1 at Aletico Mineiro despite finishing the match with nine men.
Deyverson put the visitors ahead in the 33rd minute before Fabio Santos equalized on the stroke of halftime.
Gremio lost Brazil international forward Luan in the 41st minute due to a second yellow card before striker Willian was shown a straight red for a bad foul in the 79th minute.
In Saturday’s only other match, Sao Paulo drew 2-2 at home to Ponte Preta.