Maradona: Qualification complicated for Argentina
His Brazil counterpart Dunga, meanwhile, celebrated a victory that secured the leaders of the South American group their place in next year's finals in South Africa.
"We have to go to Paraguay to see if we can win the three points," Maradona told reporters, looking ahead to Wednesday's next qualifier in Asuncion.
"It's going to be tough, complicated and all the more so after today's defeat.
"To lose to Brazil is always bad and we had hopes of winning this match to get near the World Cup."
The top four in the South American group will qualify automatically while the team finishing fifth goes into a playoff against the fourth-placed team in the CONCACAF region.
Argentina are fourth, eight points behind Brazil, and also behind Chile and Paraguay.
Maradona, who has now presided over three defeats and two wins in five qualifiers, refused to blame his players.
"I'm not complaining about my players ... We mustn't jump on (Lionel) Messi because he doesn't play alone," he said.
Messi was seen as holding the key to victory over Brazil but he was well handled by the Brazil defence.
"Overall I'm not bitter, I got very bitter in Bolivia," Maradona added, referring to a 6-1 drubbing at high altitude in April.
Dunga said he was pleased about Brazil's qualification in a match in which "technique won the day" and his players showed their work ethic.
"We have a team with great champions who work hard on the pitch. They are very hard-working players," he said.
"They are a young yet very mature team."