Brazil sneaked an injury-time winner against Chile to qualify for the world youth championship and Argentina joined them after holding hosts Colombia 1-1 in the South American under-20 championship.
Colombia, who had already qualified for the finals in the Netherlands in June, opened the scoring on Wednesday with Hugo Rodallega, the tournament's top scorer, converting an 11th minute penalty for his 10th goal in eight games.
Argentina equalised when Ezequiel Garay scored direct from a free kick in the 27th minute.
Brazil striker Rafael Sobis also scored from a free kick in the 92nd minute as they beat Chile 2-1 in Manizales. Evandro had put the Brazilians ahead with a controversial penalty in the 52nd minute, Juan Lorca equalising with seven minutes left.
With one round of matches to play, Colombia, who were backed by a noisy 30,000 crowd, lead the six-team final round with 10 points from four games. Brazil are second with nine, followed by Argentina (6), Chile and Uruguay (4) and Venezuela (0).
Chile and Uruguay face each other in their last match to decide who takes the fourth South American spot on Sunday.
