Sao Paulo, winners of the last three championships, have won four and drawn one of their last five matches to climb to eighth with 24 points, two outside the top four places that guarantee a berth in the 2010 Libertadores Cup.
Leaders Palmeiras, under former Sao Paulo title-winning coach Muricy Ramalho, have 34 points after 16 matches following a 1-0 win away to Sport Recife. They remain three points ahead second-placed Atletico Mineiro, who beat Coritiba 3-2 at home.
Sao Paulo, who appointed former Monaco coach Ricardo Gomes to replace Ramalho in June, handed seventh-placed Vitoria their first home defeat with a goal from forward Dagoberto in the 74th minute.
Dagoberto (pictured) attacked from the left after a poor clearance by the Vitoria defence, exchanging a one-two with Hugo and shooting into the top far corner for his third goal in two games.
"We didn't want to be in the situation we were in...We were getting a lot of stick but we knew that at some point it would change. Now it has changed," Dagoberto, who scored twice in the 2-1 midweek win over Gremio, told reporters.
Sao Paulo made a poor start to the previous three championships while they were also involved in the Libertadores Cup, only to recover after their elimination from the South American tournament and lift the domestic title.
"We have a very talented squad that didn't start the Brazilian championship well because they prioritised the Libertadores," coach Ricardo said.
"That's normal. Now, we are regaining our rhythm, coming into contention."
Cruzeiro, who lost this year's Libertadores Cup final to Estudiantes of Argentina last month, had two players sent off and went down 4-1 away to Gremio.
Full-back Jonathan was sent off after 19 minutes but Cruzeiro still took the lead when striker Wellington converted a penalty after he was fouled five minutes before half-time.
Six minutes into the second half, Cruzeiro forward Thiago Ribeiro was sent off for elbowing Tulio.
Gremio took full advantage of their two extra men, scoring through defender Rever, playmaker Tcheco and strikers Jonas and Argentine Maxi Lopez.
Atletico Paranaense, whose coach Waldemar Lemos quit in midweek, beat Fluminense 1-0 to send them to the bottom of the standings.
The 2008 Libertadores Cup runners-up, who sacked former Brazil coach Carlos Alberto Parreira last month, have not won in 11 matches.
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