Mark Nielsen defeated Yong Il Yoon 6-1 6-3 in the Japan 1 Masters 2 qualifying round on hard.
Nielsen M. took it in straight sets.
Mark Nielsen beat Yong Il Yoon 6-1 6-3. Umpiry, "Mark Nielsen vs Yong Il Yoon — Japan 1 Masters 2 Qualifying Round", https://umpiry.com/match/1999-06-07/nielsen-vs-yoon-japan-1-masters-2-qf?utm_source=cite (as of 7 June 1999).