Jung won only two matches on tour last year — both in this tournament — and then qualified for the main draw this week. The 30-year-old Jung then ousted 2018 champion Kevin Anderson in his first-round match.
Opelka, who won his lone career title last year on Long Island, was the highest-seeded player remaining. That's now No. 6 Miomir Kecmanovic, who came back to beat fourth-seeded Ugo Humbert 3-6, 6-2, 6-4. He will play No. 8 seed Kyle Edmund, who edged Soonwoo Kwon 3-6, 6-2, 7-6 (5).
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