London - Brazil qualified for its 19th consecutive World Cup, leaving Argentina to join Portugal and France with difficult paths to reach the 2010 World Cup.
Defending champions Italy and European champions Spain maintained their leads in Europe, while England and Germany won friendlies ahead of qualifiers on Wednesday.
And in Africa, Cameroon boosted their chances with their first victory in the final round of qualifying.
The United States came from behind at home for the second straight qualifier, defeating El Salvador 2-1 to move up one spot into second place in North and Central America and the Caribbean.
Luisao put Brazil ahead in the 24th minute at Rosario, Argentina, and Luis Fabiano scored in the 30th and 67th. Jesus Datolo scored in the 65th for Argentina, who will be under pressure to remove coach Diego Maradona.
Brazil lead South American qualifying with 30 points, three ahead of Chile and Paraguay and eight in front of Argentina with three matches remaining. The top four teams advance to the World Cup, while the No. 5 nation goes to a playoff against the No. 4 nation in North and Central America and the Caribbean.
Brazil became the seventh nation to join hosts South Africa in next year's 32-nation field, following Australia, Japan, North Korea, South Korea and the Netherlands. Argentina lost a home qualifier for the first time since a 5-0 defeat to Colombia in 1993.
Cristiano Ronaldo, the Fifa player of the year, is in danger of missing the World Cup after Portugal needed a last-minute goal by Liedson for a 1-1 draw against Denmark. Nicklas Bendtner gave the Danes the lead in the 41st minute.
Denmark leads Group one with 17 points, four ahead of Hungary, who lost 2-1 at home to Sweden when Zlatan Ibrahimovic scored in injury time. Sweden is third with 12 points, and Portugal has 10 heading into Wednesday's game against Hungary. The top team qualify from each of the nine European groups, and the best eight second-place teams go to playoffs.
France likely will have to win a playoff for a World Cup berth after a disappointing 1-1 tie with Romania at Saint-Denis.
France looked in control after Thierry Henry's 48th-minute goal, but defender Julien Escude turned the ball past his goalkeeper Hugo Llorisslid while attempting to intercept a cross seven minutes later.
"The objective is to qualify, no matter how we get there. I'm not in the habit of giving up," France coach Raymond Domenech said. "There's still everything to play for, nothing is finished yet. It will go down to the last game."
Les Bleus are second in Group seven with 14 points, four behind Serbia heading into their meeting at Belgrade on Wednesday.
The Czech Republic, who beat the United States at the 2006 World Cup, played to a 2-2 draw at Slovakia, which could qualify for its first major tournament. Substitute forward Milan Baros headed in his 34th international goal in the 84th minute for the Czechs.
Slovakia head Group three with 16 points, two ahead of Northern Ireland. The Czechs are fifth with nine.
Czech forward Jan Koller, the country's leading scorer with 55 international goals, retired from the national team after last year's European Championship, returned for this match, then said he was retiring for good from the national team.
"It's now up to the younger ones," the 36-year-old said. "I'm not good enough for it."
At Tblisi, Georgia captain Kakha Kaladze - who plays for AC Milan - headed two own goals in the 57th and 67th, giving Italy a 2-0 victory over Georgia.
"If we had to rely on two own goals to win, then so be it," Italy coach Marcello Lippi said. "But such was the way we were playing we would have scored anyway as we were creating many chances."
Italy lead Europe Group eight with 17 points heading into Wednesday's game against Bulgaria in Turin. Second-place Ireland, who trails by one point, won 2-1 at Cyprus as Robbie Keane scored in the 83rd minute with a headed goal from seven yards.
Spain routed Belgium 5-0 as David Villa scored two goals and set up two more.
Villa had a penalty kick saved, then fed Valencia teammate David Silva for the first goal in the 41st minute. Villa made it 2-0 with a long shot in the 49th and found Gerard Pique alone in front of goal one minute later.
Silva boosted the lead to 4-0 in the 68th, and Villa tapped in a shot in the 85th.
Spain, the European champions, are atop Group five with 21 points and hold a six-point lead over second-place Bosnia-Herzegovina, who won 2-0 at last-place Armenia.
At Wembley, Jermain Defoe boosted his chance to start in England's World Cup qualifier against Croatia, coming off the bench to score the second goal in a 2-1 exhibition victory over Slovenia.
Frank Lampard converted a penalty kick in the 31st minute after Wayne Rooney appeared to drag down Slovenia defender Bostjan Cesar. Zlatan Ljubijankic scored for Slovenia in the 85th with a near-post header after errors by both Glen Johnson and Joleon Lescott.
David Beckham was on the bench, but the midfielder didn't make an appearance and remained on 113 international caps, 12 shy of goalkeeper Peter Shilton's record.
Mario Gomez and Mesut Oezil scored to give Germany a 2-0 victory over World Cup hosts South Africa in a friendly match at Levekusen.
Germany lead Group four with 19 points and hosts Azerbaijan on Wednesday. Russia are one point back following Saturday's 3-0 win over Liechtenstein.
Cameroon won 2-0 at Gabon on goals by Achille Emama and Samuel Eto'o. Only the top team in each group qualifies, and the 'Indomitable Lions' need another win when they host Gabon on Wednesday.
Ivory Coast improved their record to four victories from four games, routing Burkina Faso 5-0 as Didier Drogba scored twice. - Sapa-AP