The second round at the 2019 Western and Southern Open kicked into gear Wednesday, led by the top two seeds in the women's bracket taking center stage.
No. 1 Ashleigh Barty and No. 2 Naomi Osaka are among the top contenders in Cincinnati looking to build momentum in their final tune-up for the U.S. Open starting on Aug. 26.
Here's a recap of the action from the third full day of matches at the Lindner Family Tennis Center, via WSOpen.com.
Richard Gasquet def. Federico Delbonis, 7-5, 7-6
Yoshihito Nishioka def. No. 6 Kei Nishikori, 7-6(2), 6-4
Alex De Minaur def. Reilly Opelka, 7-6(3), 6-4
Jan-Lennard Struff def. No. 5 Stefanos Tsitsipas, 6-4, 6-7(5), 7-6(8)
Andrey Rublev def. Stanislas Wawrinka, 6-4, 6-4
Diego Schwartzman def. Radu Albot, 6-4, 6-2
No. 16 David Goffin def. Guido Pella, 6-1, 7-5
No. 9 Daniil Medvedev def. Benoit Paire 7-6(2), 6-1
Miomir Kecmanovic def. No. 7 Alexander Zverev, 6-7, 6-2, 6-4
Adrian Mannarino def. Mikhail Kukushkin, 6-1, 6-3
Lucas Pouille def. Denis Shapovalov, 6-4, 6-4
No. 11 Roberto Bautista Agut def. Frances Tiafoe, 6-3, 3-6, 6-1
No. 8 Karen Khachanov def. Nick Kyrgios, 6-7(3), 7-6(4), 6-2
No. 4 Simona Halep def. Ekaterina Alexandrova, 3-6, 7-5, 6-4
No. 7 Elina Svitolina def. Elise Mertens, 6-4, 6-1
Rebecca Peterson def. Veronika Kudermetova, 2-6, 7-5, 6-2
No. 9 Aryna Sabalenka def. Saisai Zheng, 6-4, 6-3
No. 1 Ashleigh Barty def. Maria Sharapova, 6-4, 6-1
Donna Vekic def. Victoria Azarenka, 6-2, 7-5
Anett Kontaveit def. Iga Swiatek, 6-4, 7-6
No. 3 Karolina Pliskova def. Yafan Wang, 6-1, 6-3
Su-Wei Hsieh def. Jennifer Brady, 7-6, 6-3
No. 2 Naomi Osaka def. Aliaksandra Sasnovich, 7-6, 2-6, 6-2
Svetlana Kuznetsova def. Dayana Yastremska, 4-6, 7-6, 6-2
No. 16 Madison Keys def. Daria Kasatkina, 6-4, 6-1
No. 8 Sloane Stephens def. Yulia Putintseva, 2-6, 6-4, 6-3
Sofia Kenin def. Zarina Diyas, 6-4, 6-1
Kei Nishikori Upset by Yoshihito Nishioka
Kei Nishikori's post-Wimbledon struggles continued with a straight-set loss to unranked Yoshihito Nishioka, who earned his first-ever win over a top-10 opponent, Wednesday.
This was just the second tournament for Nishikori since he reached the Wimbledon quarterfinals. The Japanese star has now lost each of his last two opening matches. He was upset by Richard Gasquet in the second round at the Rogers Cup on Aug. 7.
Since returning from a wrist injury in February 2018, Nishikori has struggled to regain his previous form. The 29-year-old has just one tournament win over the past two seasons—the 2019 Brisbane International in January.
The U.S. Open has been Nishikori's best grand-slam event with two trips to the semifinals in 2016 and 2018 and a loss to Marin Cilic in the 2014 final. An early exit this week will end up being a blip on the radar of his 2019 season if another long run in the year's final grand slam happens.
Nishioka, 23, is becoming accustomed to early-round upsets. He defeated David Goffin in the second round of the Citi Open last month. This is his biggest win of the year and sets him up with another winnable match against unranked challenger Alex De Minaur in the third round.
Simona Halep Survives in Second-Round Win
Playing for the first time since retiring during the quarterfinals of the Rogers Cup, Simona Halep was pushed to the limit by Ekaterina Alexandrova before prevailing 3-6, 7-5, 6-4.
Halep was dealing with an Achilles injury that led her to withdraw prior to the second set of her match against Marie Bouzkova on Aug. 9.
"I felt [Achilles problems] since the first match here," she told reporters at the time. "Today I felt it more, so that's why I decided to retire."
Alexandrova immediately put a lot of pressure on Halep's Achilles in a match that lasted more than two hours. The Russian won seven of the last eight games in the first set to get the early advantage in the match.
Halep was on the verge of being upset when Alexandrova got within three points of taking the second set before turning things around.
On the heels of winning her first career Wimbledon title in July, Halep can become the first women's player other than Serena Williams with multiple grand slam titles in the same year since Angelique Kerber won the Australian Open and U.S. Open in 2016.
Wednesday's match won't rank among Halep's best performances of the year, but it did test her resolve in a way that could benefit her the rest of this week heading into the U.S. Open.
Ashleigh Barty Dominates Maria Sharapova
While Halep was fighting her way through the second round, top-seeded Ashleigh Barty had no problem in a 6-4, 6-1 win over Maria Sharapova.
Barty, who has already won a career-high three tournaments this year, arrived in Cincinnati looking to rebound. She lost her last two matches against unranked opponents, including a fourth-round defeat to Alison Riske at Wimbledon and a three-set loss to Sofia Kenin at the Rogers Cup.
Sharapova looked sharp early, taking a 3-1 advantage in the first set by breaking Barty's serve. It didn't last as she proceeded to drop 11 of the next 13 games. This marks the 32-year-old's fifth straight tournament in which she failed to advance past the second round.
If Barty wants to iron things out before the U.S. Open, this is a great start. The 23-year-old has never advanced past the third round in three previous appearances in this tournament.