Holders Brazil landed a tricky draw for the Copa America on Wednesday as they were thrown into Group B along with Mexico, Ecuador and Chile.
Brazil lost 1-0 in their last meeting with Mexico while Ecuador reached the last 16 at the World Cup in Germany and Chile appear set for a revival with a talented crop of young players.
The draw was kinder to hosts Venezuela, who will face Uruguay, Bolivia and Peru -- the latter pair regarded as the weakest two of the 12 teams -- in Group A.
Argentina, beaten on penalties by Brazil in the 2004 final, will face United States, Paraguay and Colombia in Group C full of potential pitfalls.
The tournament, being held in Venezuela for the first time, takes place from June 26 to July 15.
Brazil will be taking part in their first competitive matches under new coach Dunga, who replaced Carlos Alberto Parreira following their unhappy World Cup last year.
"Brazil's group is competitive and will certainly cause us difficulties," Dunga told the Brazilian Football Confederation's official web site.
"But that is a characteristic of the competition, which is always tough."
"Every team which plays against Brazil tries harder," he added. "And it's wrong to say that Chile are the weakest opponents, as some people may think. All the opponents are tough."
After a show featuring Venezuelan Llanero music, former Brazil striker Careca and former Venezuela striker Luis Mendoza took it in turns to draw the teams' names from glass pots.
The South American Football Confederation (CSF) had pre-empted the draw by hand-picking six of the teams and placing them in their respective groups on Tuesday night at a meeting behind closed doors.
Venezuela and Bolivia were placed in Group A, Brazil and Mexico in Group B and Argentina and United States in Group C, leaving only six teams to be drawn on Wednesday.
The competition will be an important warm-up for the teams ahead of the South American qualifiers for the 2010 World Cup which are due to begin later this year.
The US and Mexico, who are not part of the CSF, are taking part as guests.