Ann Li moved into the Osaka quarterfinals Thursday, beating Zeynep Sonmez 6-3, 6-1 to keep the top seed on course for a deep Japan Open run.
The American will face Austrian teenager Lilli Tagger next, with a semifinal place at stake and three United States players still competing in the singles draw.
Li finally solved a difficult opponent. The WTA’s match highlights confirmed this was her first victory over Sonmez in four meetings, reversing a previously one-sided rivalry.
That history gives the result added significance beyond the score. A comfortable win against a troublesome opponent offers a different measure of progress than simply defending seeding.
Field Level Media reported that Li pulled away from 2-2 in the opening set, winning 10 of the next 12 games and finishing in 88 minutes.
She also saved all six break points she faced and produced 22 winners against Sonmez’s 13, combining attacking output with protection of her own service games.
The break-point record helps explain why the score became so decisive. Sonmez created opportunities, but Li prevented those chances from turning into a foothold in either set.
For Li, that balance matters heading into another knockout match. Aggression can build scoreboard pressure, while escaping difficult service games keeps an opponent from interrupting that momentum.
Tennis Now reported that Li arrived at a career-high ranking of No. 25 after reaching the Wuhan quarterfinals. Thursday brought her seventh victory in nine matches.
Those results put Osaka within a broader run of strong tennis rather than making this an isolated performance. The challenge now is carrying that level into Friday.
Tagger arrives with credentials of her own. The 18-year-old beat Tereza Valentova 7-5, 6-3 to reach the last eight, according to Austrian broadcaster ORF’s tournament coverage.
The Austrian also defeated fifth seed Liudmila Samsonova 6-3, 6-3 in her opener. Two straight-set victories give Li another opponent already comfortable with the conditions in Osaka.
That makes the quarterfinal an immediate test of repeatability. Li has removed one difficult matchup, but Tagger brings fresh confidence and a separate set of problems.
The tournament is a WTA 250 event on outdoor hard courts at Utsubo Tennis Center. Its official schedule runs October 19-25, with a 32-player singles field.
Li is also part of a wider American push. Qualifier Mary Stoiana survived Moyuka Uchijima 6-2, 2-6, 6-3 and will face Katerina Siniakova for a semifinal spot.
Siniakova advanced by beating Magda Linette 6-4, 6-1. That pairing gives Stoiana a demanding next assignment after she needed three sets to eliminate the Japanese player.
Ashlyn Krueger is the third American quarterfinalist, with fourth seed Talia Gibson next. The winner of their meeting will face either Li or Tagger in the semifinals.
That draw creates a potential American semifinal, although both players must first win their quarterfinals. For now, Li’s attention belongs on the opponent directly ahead of her.
Thursday’s most encouraging feature was the way Li separated herself after an even start. Converting a tight opening into a clear win preserved control of the match.
Her next task is straightforward: reproduce that combination of attacking intent and resilience against Tagger. Another victory would move the top seed into the final four.
