OSTRAVA, Czech Republic – Top-ranked Iga Swiatek advanced to the quarterfinals of the Agel Open after Ajla Tomljanovic retired with an injury during the second set of their second-round match on Wednesday.

The Polish U.S. Open champion was leading 7-5, 2-2 when her Australian opponent retired due to a left knee injury at the indoor hardcourt event in the eastern Czech city of Ostrava.

Swiatek, who also won the French Open in June, will next face American qualifier Catherine McNally or Karolina Muchova.

Home favorite and two-time Wimbledon champion Petra Kvitova upset second-seeded Paula Badosa of Spain 7-6 (4), 6-4 to set up a quarterfinal against this year’s Wimbledon winner Elena Rybakina, who rallied to eliminate Aliaksandra Sasnovich 6-7 (5), 6-4, 7-5.

Czech players also won the last two first-round matches on the schedule.

Muchova knocked out seventh-seeded Beatriz Haddad Maia of Brazil 6-4, 6-4 and Barbora Krejcikova ousted American Shelby Rogers 6-2, 6-2 for her sixth straight victory after she won the Tallinn Open on Sunday for her first WTA title of the year.

ASTANA, Kazakhstan – Novak Djokovic delivered a near-flawless performance to ease into the second round of the Astana Open with a 6-1, 6-1 win over Cristian Garin on Wednesday as he goes for a third straight tournament title.

Djokovic dropped just six points on his serve and won the last five games to seal the win in just 62 minutes.

Djokovic is coming off a victory in Tel Aviv last week and – aside from a match at the Laver Cup – the Wimbledon champion hasn’t lost since the French Open quarterfinals.

“From the start to the end, (it was) a great performance,” Djokovic said. “Playing in a new tournament, different conditions, the first match is never easy. Obviously you are looking to see how you are going to adapt, but I did it perfectly, really, played as well as I can.”

Djokovic will next play Botic van de Zandschulp.

Top-ranked Carlos Alcaraz lost in the opening round on Tuesday in his first match since winning the U.S. Open title to capture the No. 1 spot.

Stefanos Tsitsipas reached the quarterfinals by beating 19-year-old Luca Nardi of Italy 7-6 (2), 7-6 (3). Nardi was playing just his fifth tour-level main-draw match and impressed the third-seeded Greek, who didn’t earn a single break point.

“He’s a player that can play very well in the future,” Tsitsipas said. “There weren’t any holes. I believe today he was able to sustain that level from the beginning to end, and that was extremely impressive.”

Roberto Bautista Agut also reached the quarterfinals as he followed up his first-round upset of Felix Auger-Aliassime by beating Pavel Kotov 6-1, 7-6 (5).

Marin Cilic, who lost the Tel Aviv final to Djokovic, had to come from behind to beat Oscar Otte 5-7, 7-6 (4), 6-2 in the first round to set up a round-of-16 match against Karen Khachanov.

TOKYO – Rising teenager Zheng Qinwen continued her winning run at the Toray Pan Pacific tournament, beating the sole remaining seed Veronika Kudermetova 5-7, 6-3, 7-6 (7-3) in the semifinals at the Ariake Coliseum.

In another Chinese-Russian matchup, unseeded Liudmila Samsonova overcame Zhang Shuai 7-6 (7-4), 6-2.

In a match that lasted a little over three hours, Qinwen and fourth-seeded Kudermetova traded huge ground shots, big serves and plenty of errors as they pushed each other to the limits.

Qinwen, who ousted top seed Paula Badosa in the second round, had an early advantage after breaking Kudermetova in the fourth game, but the Russian player stayed on track and broke the 19-year-old Chinese in the seventh and ninth games to secure the set.

There was just one break of serve in the remainder of the match when an error by Kudermetova gave Qinwen the advantage in the second set.

Qinwen had to save herself on many occasions, but her errors were often matched by great recoveries. The grueling match started to take its toll on Kudermetova and she needed a medical timeout for an arm problem after going 6-5 up in the final set.

World No. 36 Qinwen then served to love to set up the tiebreak and errors by Kudermetova, including a double-fault at 2-5, saw the Russian’s hopes of reaching the final unfold.

Qinwen, who will be in her first final, will need to be much more efficient to beat Samsonova, especially on her own service games. She had eight aces to Kudermetova’s six but 24 more second serves than her opponent.

“I feel so amazing to arrive in the final,” Qinwen said. “Today was a really, really difficult match. Every point was so important and there were a lot of emotions. My opponent played really good. She has a good serve and really good baseline shots and it was not easy.”

Samsonova, who won two tournaments and reached the fourth round of the U.S. Open in August, sent down an early message in her first service game against Shuai with a couple of aces that topped 180 kph.

She broke the 33-year-old Chinese in the next game with some powerful ground strokes. But she was also broken in her second service game after some unforced errors, recovering to win her next two service games to love.

World No. 28 Shuai played steady tennis but the 30th-ranked Samsonova’s errors kept the match even as the set headed to a tiebreak. A blistering forehand into the right corner gave her setpoint and she took the first set with one of her 13 aces.

After breaking Samsonova in the first game of the second set, Shuai then blew a 40-0 lead in the next game and lost her own serve.

Shuai didn’t look to have any answers as the 23-year-old Russian upped her game and she was broken in her final two service games, effectively ending the contest.

“I didn’t expect this at all,” said Samsonova, who beat Wimbledon champion Elena Rybakina in the first round and third seed Garbine Muguruza in the quarterfinals. “I came here to try to play my best and I’m in the final.

“It’s amazing. It was a very mental game because she was playing amazing so I tried to stay in there and play with her game. It was tough, but in the tiebreak I think I played better.”

Shuai is confident compatriot Qinwen is destined for greater things. “For sure some day she’ll win a Grand Slam,” she said. “When I played her, I couldn’t find where I could win points. Most of the time when you play someone, you find a way to play someone, you find a way to win points but with her, no way. She’s strong from both sides and has a big serve.”