Seong Woon Yu defeated Sung Hyuk Yu 6-3 6-4 in the Korea F7 qualifying round of 64 on hard.
Woon Yu S. took it in straight sets.
Seong Woon Yu beat Sung Hyuk Yu 6-3 6-4. Umpiry, "Seong Woon Yu vs Sung Hyuk Yu — Korea F7 Qualifying Round of 64", https://umpiry.com/match/2013-06-17/yu-vs-yu-korea-f7-q64?utm_source=cite (as of 17 June 2013).