# 1971 South American Open – Men's singles

Željko Franulović defeated Ilie Năstase 6–3, 7–6, 6–1 to win the 1971 South American Open singles competition. Franulović was the defending champion.

## Draw
### Final

| Final | Final | Final | Final | Final | Final | Final |
| | Ilie Năstase | 3 | 6 | 1 | | |
| | Željko Franulović | 6 | 7 | 6 | | |

### Section 1

| First round | First round | First round | First round | First round | First round | Second round | Second round | Second round | Second round | Second round | Second round | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Semifinals | Semifinals | Semifinals | Semifinals |
| I Năstase | 6 | 6 | 6 | | | | | | | | | | | | | | | | | |
| O Escribano | 2 | 4 | 4 | | | I Năstase | 3 | 7 | 6 | 6 | | | | | | | | | | |
| M Holeček | 6 | 7 | 6 | | | M Holeček | 6 | 6 | 3 | 0 | | | | | | | | | | |
| P Cornejo | 3 | 5 | 3 | | | | | | | | | I Năstase | 6 | 6 | 6 | | | | | |
| T Gorman | 6 | 6 | 6 | | | | | | | | | I Gulyás | 3 | 3 | 4 | | | | | |
| R Graetz | 3 | 3 | 1 | | | T Gorman | 6 | 2 | 0 | 2 | | | | | | | | | | |
| I Gulyás | 6 | 6 | 6 | | | I Gulyás | 2 | 6 | 6 | 6 | | | | | | | | | | |
| E Zuleta | 1 | 0 | 3 | | | | | | | | | | | | | | I Năstase | 6 | 7 | 6 |
| C Graebner | 6 | 6 | 6 | | | | | | | | | | | | | | J Leschly | 1 | 5 | 3 |
| N Herrero | 2 | 1 | 3 | | | C Graebner | 1 | 3 | 6 | 1 | | | | | | | | | | |
| J Leschly | 2 | 6 | 4 | 6 | 6 | J Leschly | 6 | 6 | 1 | 6 | | | | | | | | | | |
| T Vázquez | 6 | 4 | 6 | 3 | 3 | | | | | | | J Leschly | 6 | 4 | 6 | 6 | | | | |
| C Richey | 6 | 6 | 6 | | | | | | | | | C Richey | 1 | 6 | 3 | 2 | | | | |
| R Cano | 0 | 2 | 4 | | | C Richey | 3 | 6 | 4 | 7 | 6 | | | | | | | | | |
| G Vilas | | | | | | G Vilas | 6 | 4 | 6 | 6 | 2 | | | | | | | | | |

### Section 2

| First round | First round | First round | First round | First round | Second round | Second round | Second round | Second round | Second round | Second round | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Semifinals | Semifinals | Semifinals | Semifinals | Semifinals |
| Z Franulović | 6 | 6 | 6 | 6 | | | | | | | | | | | | | | | | |
| G Romani | 7 | 3 | 2 | 4 | Z Franulović | 6 | 6 | 6 | | | | | | | | | | | | |
| J Ganzábal | 6 | 6 | 6 | | J Ganzábal | 2 | 4 | 1 | | | | | | | | | | | | |
| E Soriano | 4 | 2 | 2 | | | | | | | | Z Franulović | 6 | 7 | 7 | 6 | | | | | |
| F Froehling | 7 | 6 | 6 | | | | | | | | F Froehling | 7 | 6 | 6 | 4 | | | | | |
| L Álvarez | 6 | 4 | 2 | | F Froehling | 7 | 7 | 7 | | | | | | | | | | | | |
| J Pinto Bravo | 6 | 6 | 6 | | J Pinto Bravo | 6 | 5 | 5 | | | | | | | | | | | | |
| T Koch | 1 | 4 | 3 | | | | | | | | | | | | | Z Franulović | 2 | 7 | 6 | 6 |
| R Aubone | 6 | 7 | 6 | | | | | | | | | | | | | S Smith | 6 | 6 | 1 | 3 |
| J Fillol Sr. | 2 | 6 | 4 | | R Aubone | 4 | 0 | 7 | 6 | 7 | | | | | | | | | | |
| M Lynch | | | | | M Lynch | 6 | 6 | 5 | 3 | 5 | | | | | | | | | | |
| | | | | | | | | | | | R Aubone | 2 | 4 | 4 | | | | | | |
| J Loyo-Mayo | 7 | 6 | 6 | | | | | | | | S Smith | 6 | 6 | 6 | | | | | | |
| P Rodríguez | 5 | 2 | 3 | | J Loyo-Mayo | 1 | 2 | 6 | 3 | | | | | | | | | | | |
| R Aubone | 2 | 0 | 1 | | S Smith | 6 | 6 | 2 | 6 | | | | | | | | | | | |
| S Smith | 6 | 6 | 6 | | | | | | | | | | | | | | | | | |