What to watch for in Saturday's semifinals in Austin and Merida

Following Jasmine Paolini's late-night heroics in Merida and Ashlyn Krueger's straight-sets win to become the third American into the semifinals in Austin, both the ATX Open and the Merida Open are down to four contenders.

In a week full of upsets, each draw features just one remaining seed. Even so, the storylines are plentiful as both tournaments move closer to crowning champions. In Merida, all four semifinalists are appearing in their first WTA Tour Driven by Mercedes-Benz semifinal of the season. The group includes a Top 10 player looking to reset after a disappointing Middle East swing and a 37-year-old qualifier who has yet to drop a set.

In Austin, hometown favorite and University of Texas alum Peyton Stearns is through to the semifinals after new friend Matthew McConaughey and company gave her just enough of an emotional lift to close out a grueling three-set win over Oksana Selekhmeteva. Stearns is the lone seed left in the draw, joined by fellow Americans Ashlyn Krueger and Taylor Townsend, as well as Kimberly Birrell, who outgunned Ajla Tomljanovic in an all-Australian derby to open Friday's singles action in the Lone Star State.

With play set to begin in the heart of the afternoon in Austin, here's what you need to know ahead of Saturday's semifinals at the WTA 250 in Austin and WTA 500 in Merida.

ATX Open

No. 4 Peyton Stearns vs. Kimberly Birrell

1 p.m. local, 2 p.m. ET, 7 p.m. GMT

Birrell faces a tough test against Stearns, who will have the home crowd behind her as she chases her third WTA final and first on hard courts. But the moment won't be totally unfamiliar for Birrell. Before beating Tomljanovic 6-3, 6-3 in the quarterfinals, she knocked out American Caroline Dolehide in straight sets in the second round. Stearns spent an extra hour on court in her quarterfinal, advancing only after converting her fourth match point in a 6-1, 5-7, 7-5 win over Selekhmeteva.

Stearns leads the head-to-head 1-0 after a come-from-behind win on the clay in Madrid last year, but Birrell has the stronger résumé on hard courts, reaching a pair of finals on the surface over the past two seasons. If she gets through Stearns, she'll have a chance to break through and win her first WTA title later this weekend.

Ashlyn Krueger vs. Taylor Townsend

3 p.m. local, 4 p.m. ET, 9 p.m. GMT

Beyond being an all-American semifinal on home soil, this matchup carries its own emotional weight. Townsend, a former doubles World No. 1, reached her first WTA singles semifinal by rallying past Rebeka Masarova 5-7, 6-2, 6-2 on Friday with her son watching from the stands. Meanwhile, Krueger closed out quarterfinal play in Austin with a 7-6 (5), 6-4 win over Yuan Yue. The former Top 30 player is already set to return to the Top 100 next week and could climb toward the Top 70 with a title run this weekend.

This is their first meeting at the WTA level, so Saturday's winner not only earns a spot in the final but also early bragging rights.

Merida Open

Magdalena Frech vs. (Q) Zhang Shuai

6 p.m. local, 7 p.m. ET, 12 a.m. GMT

This semifinal features two sharply contrasting paths. Frech needed three hours to defeat No. 4 seed Marie Bouzkova 6-3, 4-6, 6-3 on Friday. Having already taken out No. 7 seed Jessica Bouzas Maneiro in the second round, Bouzkova became the second straight seed to fall to the former World No. 22. The win sends Frech into her first semifinal since Guadalajara 2024, where she went on to win the title.

First, she'll have to get past an ageless wonder in Zhang. The 37-year-old had to go through qualifying after her coach supposedly forgot to submit her main-draw entry, but it hasn't mattered, as she hasn't dropped a set in five matches between qualifying and the main draw. Her run includes a win over No. 2 seed and defending champion Emma Navarro -- her third win in three meetings -- and a 6-1, 6-3 victory over fellow qualifier Victoria Jimenez Kasintseva in the quarterfinals. This is her first WTA 500 semifinal since 2022.

That year also marked her most recent WTA singles final -- a retirement loss to Beatriz Haddad Maia in Birmingham -- and her most recent WTA singles title, in Lyon over Dayana Yastremska. Zhang leads the head-to-head 2-1 over Frech, winning their most recent meeting in straight sets in Beijing 2024.

(WC) No. 1 Jasmine Paolini vs. Cristina Bucsa

7:30 p.m. local, 8:30 p.m. ET, 1:30 a.m. GMT

For the first time in her career, Paolini won a match after being bageled. She dropped the opening set 6-0 to Katie Boulter, who entered on a seven-match win streak after her Ostrava title. Paolini then survived a second set that saw her broken twice, breaking three times herself to force a decider. There, she went up 2-0, saw Boulter level at 2-2, then broke again for 4-3 before closing out a 0-6, 6-3, 6-3 win in just under two hours.

Bucsa had a similarly competitive quarterfinal but secured a straight-sets win over 2024 champion Zeynep Sonmez. With her 6-3, 6-4 victory, Bucsa -- like Zhang -- has reached the semifinals without dropping a set. Already into the doubles final with Jiang Xinyu, she is aiming for her second WTA singles final.

A win would give Bucsa her first victory over a Top 10 opponent in seven tries; all six previous losses came in straight sets. She did defeat Paolini in their most recent meeting, in Adelaide 2024, though that came before the Italian's rise into the Top 10. Paolini still leads the head-to-head 2-1.