| Alejo Mancisidor | |
| Residence: | Irun, Spain |
| Birth Date: | 1970 7, df=yes |
| Birth Place: | San Sebastián, Spain |
| Turnedpro: | 1991 |
| Plays: | Right-handed |
| Careerprizemoney: | $149,180 |
| Singlesrecord: | 5–21 |
| Singlestitles: | 0 |
| Highestsinglesranking: | No. 120 (27 Feb 1995) |
| Usopenresult: | 1R (1992) |
| Highestdoublesranking: | No. 433 (13 Jun 1994) |
Alejo Mancisidor (born 31 July 1970) is a former professional tennis player from Spain.[1]
Mancisidor played NCAA tennis while at Pepperdine University and was an All-American.[2]
He was a quarter-finalist at the Guarujá Open in 1992, with wins over Peru's Jaime Yzaga and German Marc-Kevin Goellner.[3]
The right-hander played Jeff Tarango in the opening round of the 1992 US Open and was beaten in five sets.[3]
He defeated Yzaga again in 1994, at the Bancolombia Open, when the Peruvian was ranked 19th in the world.[3]
Mancisidor coached WTA top 10 player Garbiñe Muguruza between 2010 and 2015.
| width=30 | No. | width=50 | Year | width=160 | Tournament | width=55 | Surface | width=170 | Opponent | width=120 | Score |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1. | 1994 | Bronx, United States | Hard |  Chris Woodruff | 6–2, 6–4 | ||||||
| 2. | 1994 | Natal, Brazil | Clay |  Fernando Meligeni | 6–3, 3–6, 7–5 |