Rio de Janeiro, Sep 21 (IANS): Brazil football clubs Gremio and Ecuador's Barcelona de Guayaquil advanced to the last four of the Copa Libertadores with dramatic quarterfinal victories.

Paraguay striker Lucas Barrios gave Gremio a 1-0 aggregate win in their all-Brazilian clash by heading in just after halftime in the second leg at Gremio Arena on Wednesday, reports Xinhua news agency.

Also in Brazil, forward Jonathan Alvez almost went from hero to villain as Barcelona de Guayaquil beat hosts Santos 2-1 on aggregate.

After a 1-1 draw in last week's first leg in Ecuador, Alvez put the visitors ahead with a 68th-minute strike at the Vila Belmiro stadium.

But he was shown a yellow card for excessive goal celebration and was then dismissed two minutes later following a crude tackle which drew a second caution.

Santos attacker Bruno Henrique and Barcelona's Gabriel Marques received straight red cards for an altercation in the 89th minute as the visitors held on to book their place in the semifinals.

The remaining quarterfinals scheduled for Thursday will see River Plate host Bolivia's Jorge Wilstermann in Buenos Aires and San Lorenzo visit Argentine rivals Lanus.