Complex sentence: The best qualified team between Chile, Brazil and Uruguay will qualify for Round 4 and the top 2 teams from this tournament goes to the next round of the tournament, when they will confront Argentina A in Buenos Aires, Argentina.
Split into simpler sentences: The best qualified team between Chile, Brazil and Uruguay will qualify for Round 4. And the top 2 teams from this tournament goes to the next round of the tournament, when they will confront Argentina A in Buenos Aires, Argentina.