Yeonwoo Ku vs Elena Gabriela Ruse — R16 — Korea Open

Fourth-seeded Elena Gabriela Ruse is into the Korea Open quarterfinals in Seoul, recovering from the loss of the opening set to beat Yeonwoo Ku in three sets over two hours and 15 minutes. Ku, a 23-year-old Korean ranked WTA No. 180, had reached the round of 16 with a straight-sets win over Alevtina Ibragimova. She was the more settled player early, taking all three break points she saw in the first set and winning 82 percent of her first-serve points to Ruse's 38 percent on the way to 6-2. The second set ran through five breaks of serve before it reached a tiebreak, Ruse breaking back in game 7 for 3-4 and then taking the tiebreak 7-1. Ku's serve stopped holding up after that. She double-faulted six times in the deciding set alone, eight in the match, and won 20 percent of her first-serve points as Ruse broke three times for 6-1. The margins elsewhere were thin. Each player broke serve six times, and Ruse finished with 80 of the 157 points. Ku was the more efficient on break points, converting six of 10 to Ruse's six of 14, but three of those conversions came in the set she won.