Gremio jumped up to third in the Brazilian Serie A standings as Cruzeiro continued its stranglehold on the competition.
Luiz Felipe Scolari's Gremio showed no mercy against rival Internacional, with substitute Alan Ruiz scoring twice in a 4-1 rout at the Arena do Gremio.
Gremio was on a four-game unbeaten streak prior to kick-off and it wasted little time asserting its dominance.
Luan set the tone in Porto Alegre, slotting the ball into the net from close range in the 28th minute after some neat work by Dudu.
Ramiro doubled the home side's advantage four minutes into the second half, running between two Internacional defenders and slotting the ball underneath goalkeeper Alisson.
Internacional substitute Rafael Moura pulled a goal back just past the hour-mark, but that is as good as it got for the visitor.
Ruiz - on loan from Argentine outfit San Lorenzo - came off the bench and completed the scoring with a quick-fire brace, scoring twice in six minutes.
He headed home his first goal from a corner in the 76th minute before making it two from the edge of the area six minutes later as tempers flared late on.
Gremio's big win saw it leapfrog Internacional, Atletico Mineiro and Corinthians into third position with 57 points from 33 rounds.
The two-time Serie A champion (+12) is level on points with Mineiro (+11) but ahead on goal difference and clear of Corinthians (+17) due to its superior number of wins, which is 16 to 15.
Tiago Pagnussat and Dodo led Atletico Mineiro to a 2-0 victory at Palmeiras, while Corinthians edged Santos 1-0.
Defending champion Cruzeiro is five points clear at the summit with five matches remaining after overturning a half-time deficit to beat basement side Criciuma 3-1.
Lucca's third-minute strike gave Criciuma a shock 1-0 lead at the break, but Cruzeiro stepped it up a gear in the second half with three unanswered goals.
Marcelo Moreno came off the bench and equalised in the 59th minute, before Ricardo Goulart and Willian inspired a 20th league win.
Sao Paulo is five points behind after its hard-fought 2-1 win at Vitoria, which is two points adrift of safety.
In other results, Fluminense's four-game winning streak came to an end after it lost 1-0 against Coritiba, which climbed out of the relegation zone.
Sport Recife scored twice in the final minute as it snatched a 2-2 draw at home to Flamengo and Cleo's brace helped Atletico PR to a 2-0 win over third-bottom Botafogo.
Figueirense downed Chapecoense 1-0, while Goias accounted for second-bottom Bahia 3-0.