Yexin Ma vs Kimberly Birrell — R16 — Korea Open

Second seed Kimberly Birrell beat Yexin Ma 7-5, 6-3 to reach the Korea Open quarterfinals, reversing the outcome of their only previous meeting on record: Ma won that one at the Memphis Classic in July. Ma, ranked WTA No. 174, came within a game of the opening set. She broke in game 8 for 5-3, only for Birrell to break straight back in game 9 for 4-5 and break again in game 11, then serve the set out. Birrell broke to open the second set and again in game 3. Ma broke back in game 4 for 1-3, but Birrell converted all three break points she earned in the set, and six of nine across the match to Ma's three of eight. Ma hit six aces to Birrell's one and still held only five of her 11 service games; all four of her double faults came in the second set. Birrell has yet to drop a set this week.