Defending champions Sao Paulo, the only one of the semi-finalists to have won the trophy before, need a draw at home to Mexico's Guadalajara in their second leg on Wednesday.

They won last week's first leg at the Jalisco stadium 1-0 with a late penalty converted by goalkeeper Rogerio Ceni.

Internacional have a slightly more complicated task at home to Paraguay's Libertad, needing a win after their 0-0 draw in Asuncion last Thursday.

Last year, Sao Paulo beat Atletico Paranaense 5-1 on aggregate after the final was contested by two teams from the same country for the first time in the competition's history.

Guadalajara, whose team includes five members of Mexico's World Cup squad, are still confident of ousting the titleholders.

The Chivas, the only Mexican team not to field foreigners, beat Sao Paulo home and away during the group stage, winning both games 2-1.

Their win at the Morumbi ended Sao Paulo's 30-match unbeaten home run in the Libertadores, a record which stretched back to 1987.

"We have a very powerful attack and it's unusual for Chivas to not score at least one goal in a game," said midfielder Juan Pablo Rodriguez.

Sao Paulo, the Brazilian championship leaders, crashed 4-0 at home to Santos on Sunday after resting all their regulars apart from Rogerio Ceni.

But the defeat has not dampened their spirits.

"We're going to play against Chivas in our usual way, pressing the opponents into their own half of the field," said coach Muricy Ramalho.

Guadalajara defender Diego Martinez returns after missing the first leg through suspension.

Internacional, who have seen their arch-rivals Gremio win the tournament twice, have described Thursday's match in Porto Alegre as an historic challenge.

Libertad, who have upstaged their larger neighbours Cerro Porteno and Olimpia, are still optimistic.

"Nothing is impossible," said midfielder Cristian Riveros. "I think this group is good enough to make history."