Jiri Vanek defeated Jong Sam Chung 7-6 2-6 6-3 in the Philippines Masters 4 round of 32 on hard. The upset overturned the form book — Jong Sam Chung came in leading the head-to-head 1–0. Jiri Vanek claimed a first win over Jong Sam Chung in two meetings, levelling the head-to-head at 1–1.
Vanek J. came through in three sets.
Jiri Vanek beat Jong Sam Chung 7-6 2-6 6-3. Umpiry, "Jiri Vanek vs Jong Sam Chung — Philippines Masters 4 Round of 32", https://umpiry.com/match/1997-02-15/chung-vs-vanek-philippines-masters-4-r32?utm_source=cite (as of 15 February 1997).