Diego Maradona's Argentina, having beaten Peru 2-1 at home in torrential rain, go to Montevideo on Wednesday to defend an automatic berth in the South Africa finals against a Uruguay side that turned the tables on Ecuador.
Ecuador had started the day in fourth place but their 2-1 home defeat by Uruguay left them sixth before Wednesday's visit to Chile, who took South America's third berth with a 4-2 victory in Colombia.
Brazil, who play a dead rubber away to Bolivia on Sunday, and Paraguay, whose 2-1 away win over Venezuela put them level on points with Dunga's side at the top of the group, had already qualified.
Maradona called veteran striker Martin Palermo a miracle man after his goal two minutes into stoppage time gave Argentina victory on a sodden Monumental pitch.
"I thought we were liquidated, but at that moment I forgot about Palermo," a relieved Maradona said of his desperation in the agonising minutes between Hernan Rengifo's last-minute equaliser for Peru and Palermo's winner.
FORLAN PENALTY
Forlan converted a penalty with the last kick of the game in Quito to give Uruguay their victory after recovering from a goal down but coach Oscar Washington Tabarez was quick to tell his players the job was not yet done.
"We're going to take things calmly and come out of our joy quickly to think about Argentina. We depend exclusively on a victory (on Wednesday)," Tabarez said.
Uruguay must win to swap places with Argentina and qualify for their first finals since 2002, sending their cross-river neighbours into the playoff against the team that finishes fourth in the CONCACAF region.
Ecuador, though, are not out of the running. Argentina (25 points) could even miss out altogether if Uruguay (24) and Ecuador (23) win on Wednesday.
Goals by Paraguay's Salvador Cabanas and Oscar Cardozo buried Venezuela's hopes of reaching the finals for the first time. They are not out of it mathematically but the odds are extremely poor.
"We must recognise that the Paraguayans are one of the best teams of the qualifiers," Venezuela's coach Cesar Farias told reporters.
Chileans celebrated reaching the finals for the first time since 1998 with a team revived by the methodical coaching of Argentine Marcelo Bielsa, a foreign national hero.
Bielsa, who can now dream of a better finals than 2002 when his Argentina side flopped as title favourites, showed his coaching nous with a timely substitution after half an hour in Medellin.
Chile had fallen behind but Bielsa sent on the more attacking Jorge Valdivia for playmaker Matias Fernandez and Chile went 2-1 up within four minutes and did not look back, eliminating Colombia.
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