Martin Zumpft defeated Yong Min Kwon 6-2 6-2 in the USA 1 Masters 3 round of 64 on clay.
Zumpft M. took it in straight sets.
Martin Zumpft beat Yong Min Kwon 6-2 6-2. Umpiry, "Martin Zumpft vs Yong Min Kwon — USA 1 Masters 3 Round of 64", https://umpiry.com/match/1991-03-22/kwon-vs-zumpft-usa-1-masters-3-r64?utm_source=cite (as of 22 March 1991).