2005–06 in Argentine football
The 2005–06 Argentine First Division Apertura was a nail biter. After a head-to-head finish in the last weeks Boca Juniors took the trophy home. Gimnasia de La Plata will have to wait for their first-ever championship.
The 2005–06 Argentine First Division Clausura saw Boca Juniors become the first team since River Plate in 1999–2000 to win the Apertura and the Clausura in the same season. This capped an amazing year for Boca, as they won every tournament they were eligible. Lanús were the big surprise of the Clausura, as they finished second in the league. Boca also achieved 80 points in a season for the first time since 1998/99 when they scored 89 points.
Argentina drew one of the most difficult groups in the 2006 FIFA World Cup, advanced to the second round but lost against hosts Germany in the quarter-finals.
After an abysmal season, Instituto and Tiro Federal were relegated to the Nacional B Division a few weeks before the end of the tournament. The next two worst teams in the relegation standings, Argentinos Juniors and Olimpo de Bahía Blanca, played a Promoción playoff series against Huracán and Belgrano de Córdoba, respectively, for two spots in next year's Argentine First Division. Argentinos Juniors remains in the top category after drawing with Huracán twice. Olimpo, however, were relegated to Nacional B after losing twice to Belgrano.
Torneo Apertura (''"Opening"'' Tournament)
| Position | Team | Points | Played | Won | Drawn | Lost | For | Against | Difference |
| 1 | Boca Juniors | 40 | 19 | 12 | 4 | 3 | 36 | 17 | 19 |
| 2 | Gimnasia de La Plata | 37 | 19 | 11 | 4 | 4 | 28 | 19 | 9 |
| 3 | Vélez Sársfield | 33 | 19 | 10 | 3 | 6 | 26 | 16 | 10 |
| 4 | Independiente | 32 | 19 | 8 | 8 | 3 | 34 | 22 | 12 |
| 5 | Banfield | 28 | 19 | 5 | 13 | 1 | 25 | 15 | 10 |
| 6 | River Plate | 28 | 19 | 8 | 4 | 7 | 31 | 22 | 9 |
| 7 | Estudiantes La Plata | 28 | 19 | 8 | 4 | 7 | 23 | 22 | 1 |
| 8 | Argentinos Juniors | 28 | 19 | 8 | 4 | 7 | 19 | 20 | -1 |
| 9 | San Lorenzo | 28 | 19 | 8 | 4 | 7 | 33 | 39 | -6 |
| 10 | Colón de Santa Fe | 26 | 19 | 7 | 5 | 7 | 28 | 27 | 1 |
| 11 | Racing Club | 25 | 19 | 7 | 4 | 8 | 28 | 27 | 1 |
| 12 | Olimpo de Bahía Blanca | 23 | 19 | 5 | 8 | 6 | 19 | 23 | -4 |
| 13 | Lanús | 23 | 19 | 5 | 8 | 6 | 21 | 31 | -10 |
| 14 | Arsenal de Sarandí | 22 | 19 | 5 | 7 | 7 | 23 | 24 | -1 |
| 15 | Rosario Central | 22 | 19 | 5 | 7 | 7 | 20 | 29 | -9 |
| 16 | Newell's Old Boys | 20 | 19 | 5 | 5 | 9 | 25 | 27 | -2 |
| 17 | Quilmes | 19 | 19 | 4 | 7 | 8 | 20 | 27 | -7 |
| 18 | Gimnasia de Jujuy | 18 | 19 | 3 | 9 | 7 | 23 | 30 | -7 |
| 19 | Tiro Federal | 15 | 19 | 4 | 3 | 12 | 22 | 31 | -9 |
| 20 | Instituto | 15 | 19 | 2 | 9 | 8 | 11 | 27 | -16 |
Top Scorers
| Position | Player | Team | Goals |
| 1 | Javier Cámpora | Tiro Federal | 13 |
| 2 | Leonardo Pisculichi | Argentinos Juniors | 10 |
| 2 | Rodrigo Palacio | Boca Juniors | 10 |
| 2 | Gonzalo Vargas | Gimnasia de La Plata | 10 |
| 2 | José Luis Calderón | Estudiantes de La Plata | 10 |
| 3 | Nicolás Frutos | Independiente | 9 |
| 3 | Sergio Agüero | Independiente | 9 |
| 3 | Iván Moreno y Fabianesi | Colón de Santa Fe | 9 |
| 4 | Ezequiel Lavezzi | San Lorenzo | 8 |
Relegation
Torneo Clausura (''"Closing"'' Tournament)
| Position | Team | Points | Played | Won | Drawn | Lost | For | Against | Difference |
| 1 | Boca Juniors | 43 | 19 | 13 | 4 | 2 | 37 | 14 | 23 |
| 2 | Lanús | 35 | 19 | 10 | 5 | 4 | 26 | 15 | 11 |
| 3 | River Plate | 34 | 19 | 9 | 7 | 3 | 39 | 24 | 15 |
| 4 | Gimnasia de Jujuy | 33 | 19 | 10 | 3 | 6 | 26 | 16 | 10 |
| 5 | Gimnasia de La Plata | 32 | 19 | 9 | 5 | 5 | 31 | 22 | 9 |
| 6 | Newell's Old Boys | 31 | 19 | 8 | 7 | 4 | 27 | 18 | 9 |
| 7 | Banfield | 31 | 19 | 10 | 1 | 8 | 28 | 22 | 6 |
| 8 | San Lorenzo | 28 | 19 | 7 | 7 | 5 | 15 | 14 | 1 |
| 9 | Olimpo | 26 | 19 | 7 | 5 | 7 | 22 | 22 | 0 |
| 10 | Vélez Sársfield | 25 | 19 | 5 | 10 | 4 | 21 | 18 | 3 |
| 11 | Estudiantes La Plata | 24 | 19 | 6 | 6 | 7 | 25 | 31 | -6 |
| 12 | Independiente | 23 | 19 | 6 | 5 | 8 | 18 | 18 | 0 |
| 13 | Rosario Central | 23 | 19 | 5 | 8 | 6 | 15 | 17 | -2 |
| 14 | Argentinos Juniors | 22 | 19 | 5 | 7 | 7 | 26 | 28 | -2 |
| 15 | Arsenal de Sarandí | 22 | 19 | 5 | 7 | 7 | 17 | 20 | -3 |
| 16 | Colón de Santa Fe | 20 | 19 | 5 | 5 | 9 | 19 | 26 | -7 |
| 17 | Quilmes | 20 | 19 | 5 | 5 | 9 | 11 | 28 | -17 |
| 18 | Racing Club | 19 | 19 | 5 | 4 | 10 | 14 | 24 | -10 |
| 19 | Instituto | 13 | 19 | 3 | 4 | 12 | 16 | 37 | -21 |
| 20 | Tiro Federal | 12 | 19 | 3 | 3 | 13 | 15 | 39 | -24 |
Top Scorers
| Position | Player | Team | Goals |
| 1 | Gonzalo Vargas | Gimnasia de La Plata | 12 |
| 2 | Ernesto Farías | River Plate | 11 |
| 2 | Martín Palermo | Boca Juniors | 11 |
| 3 | Ignacio Scocco | Newell's Old Boys | 9 |
| 3 | Sergio Agüero | Independiente | 9 |
| 4 | Silvio Carrario | Quilmes | 7 |
| 4 | Ezequiel Maggiolo | Olimpo de Bahia Blanca | 7 |
| 4 | Rodrigo Palacio | Boca Juniors | 7 |
Relegation
| Team | Average | Points | Played | 2003-04 | 2004-05 | 2005-06 |
| Boca Juniors | 1.807 | 206 | 114 | 75/38 | 48/38 | 83/37 |
| River Plate | 1.649 | 188 | 114 | 66/38 | 60/38 | 62/37 |
| Vélez Sársfield | 1.614 | 184 | 114 | 53/38 | 73/38 | 58/38 |
| Banfield | 1.596 | 182 | 114 | 64/38 | 59/38 | 59/38 |
| San Lorenzo | 1.491 | 170 | 114 | 62/38 | 52/38 | 56/38 |
| Newell's Old Boys | 1.421 | 162 | 114 | 51/38 | 60/38 | 51/38 |
| Gimnasia de La Plata | 1.412 | 161 | 114 | 38/38 | 54/38 | 69/38 |
| Estudiantes de La Plata | 1.377 | 157 | 114 | 44/38 | 61/38 | 52/38 |
| Lanús | 1.351 | 154 | 114 | 42/38 | 54/38 | 58/38 |
| Arsenal de Sarandí | 1.342 | 153 | 114 | 55/38 | 54/38 | 43/38 |
| Gimnasia de Jujuy | 1.342 | 51 | 38 | N/A | N/A | 51/38 |
| Racing Club | 1.333 | 152 | 114 | 50/38 | 58/38 | 44/38 |
| Rosario Central | 1.316 | 150 | 114 | 44/38 | 61/38 | 45/38 |
| Independiente | 1.298 | 148 | 114 | 44/38 | 49/38 | 55/38 |
| Colón de Santa Fe | 1.298 | 148 | 114 | 49/38 | 53/38 | 46/38 |
| Quilmes | 1.265 | 143 | 114 | 60/38 | 44/38 | 39/38 |
| Argentinos Juniors | 1.224 | 93 | 76 | N/A | 43/38 | 50/38 |
| Olimpo de Bahía Blanca | 1.149 | 131 | 114 | 39/38 | 43/38 | 49/38 |
| Instituto | 0.921 | 70 | 76 | N/A | 42/38 | 28/38 |
| Tiro Federal | 0.711 | 27 | 38 | N/A | N/A | 27/38 |
"Promoción" playoff
Argentinos Juniors remains in the Argentine First Division after a 3 - 3 aggregate tie by virtue of a "sports advantage". In case of a tie in goals, the team from the First Division gets to stay in it.Belgrano de Córdoba wins 4-2 and is promoted to Argentine First Division. Olimpo de Bahia Blanca is relegated to the Argentine Nacional B.
Lower leagues
| Level | Tournament | Champion |
| 2nd | Primera B Nacional Apertura Primera B Nacional Clausura | Godoy Cruz Nueva Chicago |
| 3rd | Primera B Metropolitana | Platense |
| 3rd | Torneo Argentino A | Villa Mitre |
| 4th | Primera C Metropolitana | Deportivo Merlo |
| 5th | Primera D Metropolitana | Ituzaingó |
Clubs in international competitions
| Team / Competition | 2005 Recopa Sudamericana | 2005 Copa Sudamericana | 2006 Copa Libertadores |
| Boca Juniors | Champions defeated  Once Caldas | Champions defeated  UNAM | did not qualify |
| Vélez Sársfield | did not play | Semifinal eliminated by UNAM | Quarterfinals eliminated by Guadalajara |
| Estudiantes de La Plata | did not play | First stage eliminated by  Banfield | Quarterfinals eliminated by  São Paulo |
| River Plate | did not play | Round of 16 eliminated by Corinthians | Quarterfinals eliminated by  Libertad |
| Newell's Old Boys | did not play | First stage eliminated by Rosario Central | Round of 16 eliminated by Vélez Sársfield |
| Rosario Central | did not play | Round of 16 eliminated by Internacional | Group Stage eliminated |