By sportswriters Spencer Musick and Lincoln van der Westhuizen

BEIJING, Oct. 4 (Xinhua) -- Round of 16 action at the ongoing China Open saw two home favorites score major upsets against current top-10 players here on Thursday.

The results set up a quarterfinal that includes two local players for the first time since the tournament was upgraded to a WTA Premier Mandatory Event in 2005.

The day started with favorite Zhang Shuai powering into the quarterfinals, upsetting world No. 3 Angelique Kerber of Germany 6-1, 2-6, 6-0.

Zhang showed strong shooting on return from the outset, breaking her opponent's first service game to race to a 3-0 lead out of the gate.

Both players held serve to 4-1 for Zhang, who got yet another break to go four set points up. She then tilted the momentum on court solidly in her favor to take the first set with ease.

The second set was much more of a struggle for both players, but Zhang came out worse, double faulting four times on the way to letting Kerber force a decider.

Zhang managed to turn things around decisively in the third, breaking all of her opponent's service games and winning 86 percent of her own first service points. Kerber coughed up 13 unforced errors in the third set to only three for Zhang.

Next up for Zhang is world No. 8 Naomi Osaka of Japan, who logged 6-1, 6-2 victory over Germany's Julia Goerges.

Osaka, the 2018 US Open women's singles champion, recovered from some shaky serving out of the gate, getting 84 percent of her returns in play on the way to the victory.

Chinese wild card entry Wang Qiang beat No. 7 seed Karolina Pliskova 6-4, 6-4. This is the second time in a little over a week that the Chinese player has beaten her more fancied opponent, after Wang moved past Pliskova in the second round of the Wuhan Open.

Buoyed by home support, Wang took the first set after breaking Pliskova's serve early in the match. Despite a series of lengthy service games, Wang was able to hold off the Czech player and closed out the first set with a blistering forehand winner.

Pliskova started the second set by winning the first break point she had been offered in the match thus far. This was followed by a crucial game where Pliskova saved two break points to take a 3-1 lead in the second set.

However Pliskova's momentum soon came to a halt as Wang came back from 4-1 down to serve for the match at 4-5. The young Chinese player upped her first serve percentage from 55 to 68 percent and took advantage of some reckless approach shots from her opponent. She won five consecutive games and booked her place in the quarterfinals.

Up next for Wang is a surging Aryna Sabalenka, who rebounded from a set down beat No. 4 seed Caroline Garcia 5-7, 7-6, 0-6.

Both players struggled to hold serve in a first set that saw seven breaks of serve. Sabalenka did herself no favours, conceding six double faults and making 23 unforced errors to hand the advantage to Garcia.

After losing serve and being down 2-5 in the second set, Sabalenka found her nerve and managed to get back to 5-5 as Garcia started to falter. The Wuhan Open champion forced a tie break and never looked back as she took the second set, and then turned up the intensity to win the final set 6-0.

Other action saw World No. 2 Caroline Wozniaki stave off an upset from Wuhan Open runner-up Annett Kontaveit, downing the Estonian in straight sets: 7-5, 6-4.

The first set saw both players fighting hard at the baseline, with Wozniacki relying on backhand slices to wear down her opponent.

Although the first set saw several chances for Kontaveit, she produced too many unforced errors (55 in total) to wrestle control of the match from Wozniacki.

With the victory, Wozniacki has officially qualified for the WTA Finals in Singapore later this year.

Wozniacki set up a meeting with Kiki Bertens in the quarterfinals, who bested Katerina Sinikova earlier today in straight sets: 6-4, 6-3.

On the men's side, Fabio Fognini of Italy logged an easy 6-4, 6-3 win over Russian No. 68 Andrey Rublev.

And in yet another upset, Tunisia's Malek Jaziri beat world No. 2 Alexander Zverev 7-6, 2-6, 6-4 in a marathon match that lasted 2 hours and 33 minutes.

Zverev paid a dear price for only taking four of the 17 break point opportunities that were presented to him. The German only conceded three break point opportunities in the whole match but Jaziri managed to convert on all three occasions.

The Tunisian could only manage to win 33 percent of his second serve points but was able to hold his nerve in a tense tie break to take a 1-0 lead heading into the second set.

Zverev improved in the second set, breaking Jaziri's serve and managing to win 80 percent of his own service points to take the second set 6-2.

The third set echoed the third with both players exchanging breaks early before settling in for a more attritional affair. This lasted until the final game of match, where the Tunisian managed to break through one last time to claim the victory.

Another match in the day session saw No. 45 Marton Fucsovics take down No. 22 Marco Cecchinato of Italy in straight sets: 6-4, 6-2.