Orešar was multiple Yugoslav youth champion in different age groups and won the Orange Bowl three times , in 1982 by defeating Boris Becker . He attended Washington & Jefferson College near Pittsburgh and was in the quarterfinals of the US Open junior tournament in 1984 . In 1985 he won in Ostend his first Challenger tournament and the semi-finals of the ATP tournament from Boston . In 1987 and 1988 he won other Challenger titles. In 1988 he was in his first ATP final, in Athens he was defeated by Horst Skoff . In the same year he was defeated in the double finals in Boston on the side of Jaime Yzaga against Jorge Lozano and Todd Witsken . He had his second and last participation in the final on the ATP World Tour in 1989 at the Swedish Open , where he lost to Paolo Canè in straight sets. He achieved his highest ranking in the tennis world rankings in 1986 with position 23 in singles and in 1989 with position 37 in doubles.
In Grand Slam tournaments, he never got past the second round. In the doubles competition, he could only qualify once for the French Open .
Orešar played 13 singles and one doubles game between 1984 and 1989 for the Yugoslav Davis Cup team . In the quarter-finals of the world group in 1988 he made the decisive point for the semi-finals with his individual victory against the Italian Francesco Cancellotti . In the semi-final match against Germany , however, he was not used, in his place played Goran Ivanišević .
Croatia
Athens
Horst Skoff
Båstad
Paolo Canè
Boston
Jaime Yzaga
Jorge Lozano Todd Witsken