| Singles | |
|---|---|
| 2005 Allianz Suisse Open Gstaad | |
| Champion |  Gastón Gaudio |
| Runner-up |  Stanislas Wawrinka |
| Score | 6–4, 6–4 |
Roger Federer was the defending champion, but did not participate this year.
Gastón Gaudio won the tournament, beating Stanislas Wawrinka in the final, 6–4, 6–4.
Nikolay Davydenko (first round, retired due to a wrist injury) Gastón Gaudio (champion)
Radek Štěpánek (second round)
David Ferrer (first round)
Ivan Ljubičić (second round) Jiří Novák (first round)
Nicolás Massú (semifinals)
Filippo Volandri (first round)| Semifinals | Final | ||||||||||||
| Q |  Răzvan Sabău | 67 | 4 | ||||||||||
| Stanislas Wawrinka | 79 | 6 | |||||||||||
| Stanislas Wawrinka | 4 | 4 | |||||||||||
| 2 | Gastón Gaudio | 6 | 6 | ||||||||||
| 7 | Nicolás Massú | 3 | 2 | ||||||||||
| 2 | Gastón Gaudio | 6 | 6 | ||||||||||
| First round | Second round | Quarterfinals | Semifinals | ||||||||||||||||||||||||
| 1 | N Davydenko | 6 | 1r | ||||||||||||||||||||||||
 S Sargsian | 1 | 0 | S Sargsian | 4 | 4 | ||||||||||||||||||||||
| WC | M Lammer | 6 | 2 | 3 | Q | R Sabău | 6 | 6 | |||||||||||||||||||
| Q | R Sabău | 3 | 6 | 6 | Q | R Sabău | 0 | 7 | 7 | ||||||||||||||||||
| I Andreev | 5 | 3 | P Starace | 6 | 5 | 5 | |||||||||||||||||||||
| F López | 7 | 6 | F López | 66 | 0 | ||||||||||||||||||||||
| P Starace | 6 | 63 | 7 | P Starace | 78 | 6 | |||||||||||||||||||||
| 6 | J Novák | 3 | 77 | 5 | Q | R Sabău | 67 | 4 | |||||||||||||||||||
| 3 | R Štěpánek | 78 | 6 | S Wawrinka | 79 | 6 | |||||||||||||||||||||
| WC | Y Allegro | 66 | 1 | 3 | R Štěpánek | 77 | 4 | 4 | |||||||||||||||||||
 P Kohlschreiber | 3 | 5 | Q | F Čermák | 65 | 6 | 6 | ||||||||||||||||||||
| Q | F Čermák | 6 | 7 | Q | F Čermák | 4 | 65 | ||||||||||||||||||||
| F Verdasco | 6 | 6 | S Wawrinka | 6 | 77 | ||||||||||||||||||||||
| Q | J Pospíšil | 2 | 4 | F Verdasco | 6 | 4 | 68 | ||||||||||||||||||||
| S Wawrinka | 6 | 2 | 6 | S Wawrinka | 3 | 6 | 710 | ||||||||||||||||||||
| 8 | F Volandri | 1 | 6 | 4 | |||||||||||||||||||||||
| First round | Second round | Quarterfinals | Semifinals | ||||||||||||||||||||||||
| 7 | N Massú | 77 | 77 | ||||||||||||||||||||||||
| T Behrend | 64 | 63 | 7 | N Massú | 7 | 2 | 6 | ||||||||||||||||||||
| J Hernych | 7 | 6 | J Hernych | 5 | 6 | 4 | |||||||||||||||||||||
| Q |  H Armando | 5 | 3 | 7 | N Massú | 6 | 6 | ||||||||||||||||||||
 L Horna | 710 | 6 | L Horna | 4 | 4 | ||||||||||||||||||||||
| T Zíb | 68 | 4 | L Horna | 6 | 6 | ||||||||||||||||||||||
| A di Mauro | 6 | 1 | 6 | A di Mauro | 3 | 4 | |||||||||||||||||||||
| 4 | D Ferrer | 4 | 6 | 3 | 7 | N Massú | 3 | 2 | |||||||||||||||||||
| 5 | I Ljubičić | 6 | 6 | 2 | G Gaudio | 6 | 6 | ||||||||||||||||||||
 R Mello | 3 | 2 | 5 | I Ljubičić | 64 | 3 | |||||||||||||||||||||
 S Koubek | 77 | 65 | 66 | A Seppi | 77 | 6 | |||||||||||||||||||||
| A Seppi | 65 | 77 | 78 | A Seppi | 4 | 6 | 65 | ||||||||||||||||||||
| R Schüttler | 78 | 2 | 3 | 2 | G Gaudio | 6 | 1 | 77 | |||||||||||||||||||
| D Sanguinetti | 66 | 6 | 6 | D Sanguinetti | 2 | 2 | |||||||||||||||||||||
| WC | G Bastl | 5 | 2 | 2 | G Gaudio | 6 | 6 | ||||||||||||||||||||
| 2 | G Gaudio | 7 | 6 | ||||||||||||||||||||||||
Rafael Nadal was the defending champion, but did not participate this year.
Rafael Nadal was the defending champion, but chose not to participate that year.
Carlos Moyá was the defending champion but lost in the final 6–4, 6–1 against Guillermo Coria.
Gastón Gaudio defeated Mariano Puerta 6–4, 6–4 to win the 2005 ATP Buenos Aires singles competition. Guillermo Coria was the champion but did not defend his title.
Gastón Gaudio was the defending champion, but did not participate this year.
Gustavo Kuerten was the defending champion but did not compete that year.
Fernando González was the defending champion.
Gastón Gaudio was the defending champion, but lost in the second round this year.
Gastón Gaudio was the defending champion but lost in the quarterfinals to Flávio Saretta.
In the men's singles final, Gastón Gaudio defeated Tommy Robredo with a score of 6–1, 2–6, 6–1.
Juan Ignacio Chela was the defending champion but lost in the second round to Rubén Ramírez Hidalgo.
Jiří Novák was the defending champion but did not compete that year.
Carlos Moyá was the defending champion but lost in the third round to Gastón Gaudio.
Gastón Gaudio was the defending champion but lost in the quarterfinals to Richard Gasquet.
Juan Ignacio Chela and Gastón Gaudio were the defending champions. Chela participated with Tommy Robredo this year, finishing runner-up. Gaudio did not participate this year.
Gastón Gaudio was the defending singles champion of the Torneo Godó men's tennis tournament, but lost in the quarterfinals this year.
Gastón Gaudio was the defending champion, but lost in the quarterfinals to Agustín Calleri.
In the 2005 Austrian Open Singles, Nicolás Massú was the defending champion, but lost in the semifinals to Fernando Verdasco.
Mariano Zabaleta was the defending champion, and defended his title defeating Gastón Gaudio 6–1, 4–6, 7–6(7–4) in the final.
Guillermo Coria was the defending champion, but did not compete this year.