Katie Boulter of Great Britain and German qualifier Jule Niemeier were early winners as first-round singles play began Monday in the $922,573 Cymbiotika San Diego Open at Barnes Tennis Center.
Boulter defeated Lesia Tsurenko, 6-3, 6-1, in one hour, 11 minutes for her first victory over the Ukrainian after three losses. Boulter will face second-seeded Beatriz Haddad Maia in the second round in the first meeting between the two.
Each of the top four seeds received first-round byes.
Niemeier defeated Varvara Gracheva of France, 6-3, 6-0, in 54 minutes and will face top-seeded American Jessica Pegula is the second round in the first meeting between the two.
Sixth-seeded Marta Kostyuk is the lone seeded player set to play Monday. The Ukrainian will face American qualifier Ann Li in the final match of the day on the Barnes Stadium court, beginning no earlier than 7 p.m.
Li earned her spot in the 28-player main draw by defeating fellow American Kayla Day, 6-3, 6-0, in 1 hour, 9 minutes on the second and final day of qualifying play Sunday. Li had lost all three of her previous matches against Day.
“She’s always a tough opponent,” the 23-year-old Pennsylvanian said. “I’m glad to pull through and be in the main draw. No expectations, really. I’m just trying to be better, trying to improve, just trying to build on the momentum and see where it goes.”
Li is 167th on the Women’s Tennis Association rankings. Her latest victory in a main draw singles match in a WTA tournament was on Oct. 23, when she defeated Heather Watson of Great Britain, 4-6, 6-1, 6-3, in the first round of the Abierto Tampico in Tampico, Mexico.
Since then, Li has lost in the first round of the Dow Tennis Classic, lost in qualifying for the Workday Canberra International and Australian Open and retired in a first-round match of the Puerto Vallarta Open in Puerto Vallarta, Mexico last Monday after losing the first game of the third set.
Li was a 7-5, 1-6, 6-3 winner over Kostyuk in their only previous meeting, the final of the Bellatorum Resources Pro Classic, an $80,000 Women’s U.S. Tennis Association Pro Circuit event in Tyler, Texas on Nov. 1, 2020.
The 21-year-old Kostyuk is ranked 34th, six spots below her career best achieved Jan. 28 after she reached the quarterfinals of the Australian Open, losing to American Coco Gauff, 7-6 (6), 6-7 (3), 6-2.
Kostyuk will be playing for the first time since retiring from her second-round match of the Qatar TotalEnergies Open on Feb. 13, when she was trailing Russian Anastasia Pavlyuchenkova, 2-1.
Monday’s singles winners are guaranteed at least $13,590 while the losers will receive $9,820.
The tournament is set to conclude Sunday. The winner will receive $142,000.
City News Service contributed to this article.