Marcos Ondruska
| Country (sports) |  South Africa  South Africa |
|---|---|
| Born | 18 December 1972 Bloemfontein, South Africa |
| Height | 1.83 m (6 ft 0 in) |
| Turned pro | 1989 |
| Plays | Right-handed (1-handed backhand) |
| Prize money | $1,835,129 |
| Singles | |
| Career record | 118–147 |
| Highest ranking | No. 27 (10 May 1993) |
| Grand Slam singles results | |
| Australian Open | 4R (1996) |
| French Open | 3R (1991) |
| Wimbledon | 2R (1993, 1994, 1997) |
| US Open | 3R (1994, 1995) |
| Doubles | |
| Career record | 113–133 |
| Career titles | 4 |
| Highest ranking | No. 34 (2 August 1993) |
| Grand Slam doubles results | |
| Australian Open | SF (1993) |
| French Open | 2R (1993) |
| Wimbledon | 3R (1993, 1994, 1995) |
| US Open | 3R (1999) |
Marcos Ondruska (born 18 December 1972 in Bloemfontein) is a former tennis player from South Africa, who turned professional in 1989. He represented his native country at the 1996 Summer Olympics in Atlanta, Georgia, where he defeated Goran Ivanišević in the first round before falling to Norway's Christian Ruud. The right-hander won four career titles in doubles, and reached his highest singles ATP-ranking on 10 May 1993, when he became the number 27 of the world.
Has a 13-7 career Davis Cup record in 11 ties.
Doubles finals
Titles (4)
| Legend |
| Grand Slam (0) |
| Tennis Masters Cup (0) |
| ATP Masters Series (0) |
| ATP Tour (4) |
| No. | Date | Tournament | Surface | Partner | Opponents in the final | Score |
|---|---|---|---|---|---|---|
| 1. | 1996 | Auckland | Hard |  Jack Waite
|
 Jonas Bjorkman Brett Steven
|
walkover |
| 2. | 1996 | Palermo | Clay |  Andrew Kratzmann
|
 Cristian Brandi Emilio Sanchez
|
7–6, 6–4 |
| 3. | 1996 | Tel Aviv | Hard | Grant Stafford
|
 Noam Behr Eyal Erlich
|
6–3, 6–2 |
| 4. | 1997 | Long Island | Hard |  David Prinosil
|
Mark Keil T.J Middleton
|
6–4, 6–4 |