Women’s top seed Ashleigh Barty held off Anett Kontaveit as the Estonian served for victory before the top seed scraped a 4-6, 7-5, 7-5 triumph into the quarter-finals at WTA Cincinnati Masters.

The win keeps the Australian in the chase for a possible return to the WTA number one ranking, which she lost to Naomi Osaka on Monday. Barty needs to reach Sunday’s final in order to regain the ranking summit.

“It was a little bit scrappy at times today but proud of the way we were able to fight and hang in there right until the end,” said the reigning Roland Garros champion.

“It was more about the fight today than the tennis.”

Barty, who earlier eliminated five-time Grand Slam winner Maria Sharapova, will play Friday against Maria Sakkari of Greece, a 6-7 (4/7), 6-4, 6-4 winner over ninth seed Aryna Sabalenka.

Japanese second seed Osaka advanced 7-6 (7/3), 5-7, 6-2 over Hsieh Su-Wei, who defeated Osaka this year in Miami.

Osaka, current holder of the US and Australian Open titles, is playing the event for the fist time after failing to qualify on her only previous attempt in 2016.

2017 US Open finalist Madison Keys sent Wimbledon champion Simona Halep out 6-1, 3-6, 7-5.

Halep, last year’s Cincinnati runner-up, will go to the US Open with just three post-Wimbledon competitive matches.

Double Grand Slam champion Svetlana Kuznetsova beat 2017 US Open winner Sloane Stephens 6-1, 6-2.

Venus Williams won three matches in a row for the first time since March as she defeated Donna Vekic 2-6, 6-3, 6-3.

Third round results on Thursday at the WTA Cincinnati Masters (x-denotes seeding):

Ashleigh Barty (AUS x1) bt Anett Kontaveit (EST) 4-6, 7-5, 7-5

Maria Sakkari (GRE) bt Aryna Sabalenka (BLR x9) 6-7 (4/7), 6-4, 6-4

Karolína Plíšková (CZE x3) bt Rebecca Peterson (SWE) 7-5, 6-4

Svetlana Kuznetsova (RUS) bt Sloane Stephens (USA x8) 6-1, 6-2

Venus Williams (USA) bt Donna Vekic (CRO) 2-6, 6-3, 6-3

Naomi Osaka (JPN x2) bt Hsieh Su-wei (TPE) 7-6 (7/3), 5-7, 6-2

Madison Keys (USA x16) bt Simona Halep (ROM x4) 6-1, 3-6, 7-5

(With AFP inputs)