One of the main questions i see asked in forums is how is the league system, what is Apertura and Clausura, how are relegations decided, how do teams qualify to Copa Libertadores/Sudamericana, so i decided it could be interesting to start the blog writing about it.
In Argentina there are two tournaments per season : Apertura (played from August to December) and Clausura (February to June), so, there are two champions per season. No final game between them, just two champions.
Each tournament has 19 rounds where the 20 teams play each other once and the team at the top of the standings at the end, is the champion.
The fixture of each season is drawn before Apertura, and Clausura uses the same schedule with reversed home teams.
If two teams have the same points in the 1st place after the 19 games, they play a game in neutral field to decide who will be the champion. If 3 or more teams are tied, then a mini tournament is played between this teams, where each team plays against the others once, all games in neutral field. The team with more points (or better goal difference in this mini tournament games if they tie in points), is the champion.
Since the Apertura/Clausura system was introduced in the 1990/1991 season, only twice the tournament ended with more than one team at the top (Apertura 2006 : Boca and Estudiantes, and Apertura 2008 : Boca, San Lorenzo and Tigre).
Next subject, one of the most difficult things to understand for people not involved in this league : how are relegations decided ?