Boca Juniors won the Apertura championship for their 29th national title after a three team playoff with Tigre and San Lorenzo.
Both Gimnasia and Esgrima (J) and Racing won their playoff matches and retained their status in top-flight football.
Since San Lorenzo, Tigre and Boca Juniors ended the tournament with the same number of points, a three-way playoff was played to determine the champions.
Source: Scorer Stats (in Spanish) The Torneo Clausura (English: Closing Tournament) began on February 6, 2009 and ended on July 5, 2009.
Every club had its points earned divided by the number of matches played and an average (Spanish: promedio) was determined.
Source:AFA Gimnasia y Esgrima (LP) remained in the Argentine First Division after a 3–3 aggregate tie by virtue of a "sports advantage".