World No. 4 Elina Svitolina pulled out of the WTA Hong Kong Open on Thursday with a leg injury, giving American Nicole Gibbs a walkover into the quarter-finals.
The top seed from Ukraine has been carrying a right groin strain which was heavily strapped as she laboured to a first-round victory over Zarina Diyas on Tuesday.
Svitolina said she sustained the injury during her mammoth 3hr 21min 6-7, 7-5, 7-6 quarter-final defeat in Beijing last week to the eventual champion there Caroline Garcia.
“I picked up the injury a little bit in Beijing,” she said.
“It’s the groin. All the time when I go for wide shots or stretch I feel it.
“I will probably do some scans now to see how it is, because you know I have Singapore. It’s a tough decision because I really wanted to play here.”
Svitolina has been enjoying the best season of her career, winning five times on the WTA Tour in Taipei, Dubai, Istanbul, Rome and Toronto while achieving a career-high ranking of three.
The Ukrainian has just 10 days to recover her fitness before top eight-ranked players battle it out in the season-ending WTA Tour finals in Singapore.
The top seed Svitolina’s withdrawal means Gibbs will play compatriot Jennifer Brady on Friday.
Big-hitting Brady, ranked 70, easily overcame an out-of-sorts Shuai Zhang 6-3, 6-4 in just over an hour.
Brady smacked down seven aces to overpower the world No. 31, whose inconsistent serve was broken three times in the second set alone.
“I started strongly with the first break and was aggressive,” said Brady.
“My strengths are my serve, my forehand and my athleticism. I can play from every part of the court. I knew she would come back aggressively in the second set so I’m happy with the win.”
It left Wang Qiang as the sole Chinese representative in the draw after she breezed past Thailand’s Luksika Kumkhum 6-4, 6-4.
Wang will face former US Open champion Sam Stosur of Australia on Friday for a place in the semi-finals.
Maria Sharapova surged into the Tianjin Open quarter-finals as she pursues her first tournament victory since her return from a doping ban.
The Russian former world No. 1 defeated Magda Linette of Poland 7-5, 6-3 and will next play either Swiss qualifier Stefanie Voegele or fifth seed Yulia Putintseva of Kazakhstan.
The 30-year-old Sharapova has been on the comeback trail since April after serving a 15-month suspension for taking the banned substance meldonium.
Sharapova, a five-time major-winner, is now ranked a lowly 86 in the world and she needed a wildcard to enter the Tianjin tournament.
She saw off 71st-ranked Linette in just over 98 minutes to reach only her second quarter-final since her return to action.
Meanwhile, Johanna Konta has withdrawn from the Kremlin Cup next week, meaning Caroline Garcia has secured the eighth and last berth in the WTA Finals.
Konta still is not ready to play after a left-foot injury forced her out of the Hong Kong Open this month.
Konta was ranked a career-high fourth in July after reaching the Wimbledon semifinals but the British player has lost her first match at her last five tournaments, sending her slipping to 10th.
Garcia has won tournaments in Beijing and Wuhan to overtake Konta.
Konta’s withdrawal from Moscow makes Garcia the first Frenchwoman since 2006 to qualify directly for the end-of-season finals, which begin on Oct. 22 in Singapore.
The other qualified players are new No. 1 Simona Halep, Garbine Muguruza, Karolina Pliskova, Elina Svitolina, Venus Williams, Caroline Wozniacki and Jelena Ostapenko.
On the men’s tour, Rafael Nadal underlined his status as world NO. 1 and the man to beat at the Shanghai Masters as he powered into the quarter-finals at the expense of Fabio Fognini.
The 31-year-old Spaniard was comfortable in seeing off the 28th-ranked Italian 6-3, 6-1 and will play sixth seed Grigor Dimitrov in the last eight.
Top seed Nadal is chasing a seventh title this season, but a career-first Shanghai Masters.
Roger Federer avoided a potential banana skin in outclassing the Ukrainian qualifier Alexandr Dolgopolov.
The Swiss legend looked rusty in his opener on Wednesday but was closer to his fluent best as he swatted away Dolgopolov 6-4, 6-2 in a swift 61 minutes on court.
Juan Martin del Potro advanced to the quarter-finals by overcoming third-seeded Alexander Zverev 3-6, 7-6, 6-4 on Thursday.
Del Potro required four match points – two on Zverev’s serve in the ninth game, two on his own serve in the 10th – to win this first encounter career against the German.
Del Potro, who lost his serve for the only time in the match in the second game, won nine of his 15 service games at love.
“I’m happy with my success as I played one of the good guys on tour, he’s been playing so good this season,” Del Potro said. “This was a positive for me looking to the future.”
Zverev, who was in the hunt for a sixth ATP title of the season, lost his composure after netting a backhand to surrender his serve in the fifth game of the third set to the Argentine.
Zverev whacked his racket on the court. That didn’t satisfy his anger so he kept smashing the racket courtside until it was a mangled mess.
“For me, it’s impossible to lose a match when I’ve only been broken one time,” Zverev said. “The game where he broke me I was up 40-15 and I was just unfocused there.”
Del Potro, a 2013 Shanghai finalist, was aware he made a likely permanent impact by breaking Zverev’s serve.
“I saw his frustration, for sure,” he said. “He’s still very young and has to keep learning. He has everything to be in the top of the game.”
Earlier, Dimitrov of Bulgaria got past Sam Querrey of the US 6-3, 7-6 in the round of 16. Fourth-seeded Marin Cilic defeated another American, Steve Johnson, 7-6, 6-4.