Valentin Sanon defeated Konstantin Don Gruber 3-6 6-1 6-3 in the Central America 4 qualifying round on hard.
Sanon V. came through in three sets.
Valentin Sanon beat Konstantin Don Gruber 3-6 6-1 6-3. Umpiry, "Valentin Sanon vs Konstantin Don Gruber — Central America 4 Qualifying Round", https://umpiry.com/match/2001-01-08/gruber-vs-sanon-central-america-4-qf?utm_source=cite (as of 8 January 2001).