By JOHN FREEMAN

Seventeen-year-old qualifier Clervie Ngounoue won two qualifying matches over the weekend. She was looking to win her first WTA main draw match in Monday’s opening round of the 2023 Cymbiotika San Diego Open at Barnes Tennis Center.
But fellow American Katie Volynets (above) had other ideas as the 21-year-old right-hander from Walnut Creek got past Ngounoue with a hard-fought come-from-behind 2-6, 6-4, 6-2 first-round victory in just over two hours.
Volynets captured the USTA Billie Jean King Girls’ 18s National Championship in 2019, the same event Ngounoue won last month, also held at Barnes Tennis Center.
“I thought coming in here that I would have the edge, having won it when I was 17,” said Volynets. “I know she plays well here, so I’m happy I was able to get through.”
Ngounoue, a hard-hitting right-hander from Washington, D.C., competed in her first WTA 500 main draw after launching her pro career.
“I was expecting a fight and I knew she’s a fighter,” Ngounoue said. “She played really well, but I think I learned a lot of things to take from it.”
Earlier Monday, following a two-hour and 15-minute rain delay that halted play at 3-3 in the third set, Russia’s Anastasia Potapova recorded a 6-2, 5-7, 6-4 win over Alycia Parks of the United States, in the event’s first match of the day.
“It was very tough from the first point,” said Potapova. “The actual temperature didn’t seem so hot, but it felt very hot, especially for a long match. I’ve played in a lot worse weather, so I enjoyed it.”
In the evening session, qualifier Aliaksandra Sasnovich of Belarus pulled off the upset of the day as she ousted fifth-seeded Belinda Bencic of Switzerland 6-3, 3-6, 6-2 in two hours and 17 minutes.
The final match of the night session came to a close at 12:05 a.m., as Anhelina Kalinina of Ukraine eliminated Karolina Pliskova of Czech Republic 7-6 (4), 0-6, 6-3 in 2 hours and 31 minutes.
Top-seeded Ons Jabeur of Tunisia, the event’s highest-ranked player at No. 7, received a first-round bye and will play her first match on Wednesday.
First-round matches continue on Tuesday as last year’s semifinalist Danielle Collins is scheduled to face fellow American Louisa Chirico, a qualifier from Harrison, N.Y.
Wild-card entrant Leyla Fernandez of Canada, a finalist at the 2021 U.S. Open, will meet 7th seeded Beatrice Haddad Maia of Brazil.
Former U.S. Open champion Sloane Stephens will take on Elise Mertens of Belgium, who fell in the second round of this year’s U.S. Open, losing in three sets to eventual winner Coco Gauff.
The six-day Cymbiotika San Diego Open is a WTA 500 event, with a total purse of $780,637, including $120,150 for the singles champion and 500 WTA ranking points. The event concludes with Saturday’s finals.

Results – Monday, Sept. 11
R16 – [1] B. Krejcikova (CZE) / K. Siniakova (CZE) d. C. Garcia (FRA) / D. Schuurs (NED) 76(4) 75
R16 – T. Mihalikova (SVK) / Y. Xu (CHN) d. O. Kalashnikova (GEO) / M. Kolodziejova (CZE) 76(6) 46 10-6
R16 – [4] L. Kichenok (UKR) / J. Ostapenko (LAT) d. S. Santamaria (USA) / I. Shymanovich 57 76(5) 11-9
R32 – A. Potapova d. A. Parks (USA) 62 57 64
R32 – [WC] K. Volynets (USA) d. [Q] C. Ngounoue (USA) 26 64 62
R32 – [Q] C. Osorio (COL) d. [Q] M. Frech (POL) 63 16 64
R32 – [Q] E. Navarro (USA) d. J. Paolini (ITA) 75 60
R32 – [Q] A. Sasnovich d. [5] B. Bencic (SUI) 63 36 62
R32 – A. Kalinina (UKR) d. K. Pliskova (CZE) 76(4) 06 63

Schedule – Tuesday, Sept. 12
BARNES STADIUM starts at 11:30 a.m.
[Q] L. Chirico (USA) vs D. Collins (USA)
[WC] S. Kenin (USA) vs [6] V. Kudermetova
After suitable rest M. Kostyuk (UKR) / A. Parks (USA) vs [WC] D. Collins (USA) / C. Vandeweghe (USA)
NB 5:30 PM S. Stephens (USA) vs E. Mertens (BEL)
[7] B. Haddad Maia (BRA) vs [WC] L. Fernandez (CAN)

COURT 2 starts at 11:30 a.m.
M. Linette (POL) vs M. Kostyuk (UKR)
NB 1:30 PM [8] E. Alexandrova vs J. Ostapenko (LAT)
[3] H. Chan (TPE) / G. Olmos (MEX) vs M. Kato (JPN) / A. Sutjiadi (INA)
After suitable rest E. Alexandrova / A. Sasnovich vs C. Dolehide (USA) / C. Liu (USA)
A. Guarachi (CHI) / M. Niculescu (ROU) vs [2] S. Aoyama (JPN) / Z. Yang (CHN)