San Francisco Frontiers - Swiatek coasts through Wuhan debut while heat wilts players

Swiatek, who had an opening-round bye, eased past the Czech Republic's Marie Bouzkova 6-1, 6-1 to book a third-round clash with Belinda Bencic or Elise Mertens.

After her win, Swiatek called on organisers to take player safety into account when scheduling matches on the outside courts, where there is no roof that can be closed to control the temperature.

"I feel like it's getting hotter in different places over the years," she said. "I'm just trying to use my experience, recover well between the points, and just spend all my energy on having the best quality possible. But for sure it's a challenge."

High temperatures above 30 Celsius (86 Fahrenheit) forced organisers to put the heat rule into effect on Monday, where play was suspended on the outside courts.

The heat rule was also in effect on Tuesday between 12:30 and 17:30 but no matches were suspended.

"I'm happy I didn't play yesterday because I think it was too much for most of the players," said Swiatek, who needed just 79 minutes to get through her match.

"On centre court, I think it's a little bit cooler with the air-conditioning and everything, but I hope the other matches will be scheduled at a time where girls can compete, rather than just die on the court."

Earlier, Raducanu had her blood pressure and other vitals checked before retiring with dizziness from her first-round match when down 6-1, 4-1 to American Ann Li.

The British world number 30 appeared to be struggling with the conditions as the temperature soared.

The 2021 US Open champion received medical attention five games into the second set.

She made the call to retire, sending Li into a second-round meeting with ninth-seeded Ekaterina Alexandrova.

The heat rule allows players to take a 10-minute break between the second and third sets, and means the tournament can partially or fully close the centre-court roof to protect players.

Ostapenko, who was scheduled on a roofless outside court, also had her vitals checked and was feeling unwell before she retired, citing heat illness, while down 6-0, 2-1 to Sorana Cirstea.

Meanwhile, four-time major champion Naomi Osaka claimed her first victory at the Wuhan Open with a hard-fought 4-6, 7-5, 6-3 victory over Canada's Leylah Fernandez.

In a tense two-hour 30-minute affair, the 11th-seeded Osaka fired 41 winners and 56 unforced errors.

Osaka, who is playing in Wuhan for the first time since 2017, will take on last week's Beijing finalist Linda Noskova in the second round.

"Mentally it was just really tough for me today," said Osaka. "And I think it's a part of the season that's just tough. But I think I'm, like, really happy to have gotten through it, and I think it'll be easier from now on."

Chinese wildcard Zhang Shuai, ranked 142 in the world, stunned 14th-seeded Emma Navarro 6-2, 2-6, 6-3. It is Zhang's second victory over Navarro in as many meetings, and her first top-20 win of the season.

The 36-year-old will take on Cirstea in round two.

H.Reyes--SFF