Brazil's Ronaldinho laughs during a training session yesterday. Brazil face Chile in a World Cup 2010 qualifying match tomorrow in Chile. - AP

BUENOS AIRES, Argentina (AP):

ARGENTINA HOST Para-guay today with the chance to go to the top in South American World Cup qualifying, if they can regain their winning form.

A victory in Buenos Aires will snap Argentina's three-match winless streak, allowing them to overtake the Paraguayans atop the 10-team standings. Argentina enter the match with 11 points, two less than Paraguay.

In other key matches this weekend, third-place Colombia will face No. 6 Uruguay, while No. 4 Chile will host No. 5 Brazil. Only the top four teams will automatically qualify for the 2010 World Cup in South Africa.

Led by Lionel Messi, Argentina won the Olympic tournament last month, but in South American qualifying they are coming off a 2-1 loss to Colombia, a 1-1 draw against Ecuador and a 0-0 draw with Brazil.

Paraguay were unbeaten until losing 4-2 to Bolivia in the high altitude of La Paz in their last match.

"The Paraguayans are very tough," Argentina striker Carlos Tevez said. "But we will try to reach the level we want, with good passing and good football."

Messi, Sergio Aguero, Juan Roman Riquelme and Angel Di Maria are some of the Olympic champions summoned by coach Alfio Basile for today's qualifier.

Paraguay will be missing two important players with forwards Roque Santa Cruz and Salvador Cabanas out injured. Coach Gerardo Martino is likely to replace them with Oscar Cardozo and Nelson Haedo Valdez.

dunga's job on the line

Brazil coach Dunga will have his job on the line in the match against Chile tomorrow in Santiago. Brazil, who still have never won gold at the Olympics after taking bronze in Beijing, are coming off a 2-0 loss to Paraguay and a 0-0 draw with Argentina in Cup qualifying.

Dunga is being heavily pressured by local media and fans, and another setback could prompt the Brazilian football federation to replace him.

Dunga will be able to count on Ronaldinho and Robinho, but Kaka was not selected because of a lingering knee injury.

"The situation we are in gives us more motivation to try to win our next matches and secure a spot among the top four nations," Ronaldinho said.

Chile, led by Argentine coach Marcelo Bielsa, could reach second place in the standings if they beat the Brazilians at home. They have 10 points, one more than Brazil.

Colombia, the only unbeaten team so far, will host Uruguay in Bogota today with a chance to improve on their 10 points and remain close to the leaders.

Colombia have the best defence, with only two goals allowed, while Uruguay have scored the most goals with 15, thanks in part to their 6-0 rout of Peru in the last round.

The Colombians will be missing injured forward Edixon Perea, who is likely to be replaced by veteran Milton Rodriguez.

"We hope the strikers can come through to help us find the goals we need," Colombia coach Jorge Luis Pinto said.

In other matches, Ecuador will host Bolivia and Venezuela will play at Peru.