TWO Grand Slam winners will face off in the fourth round of the China Open after former world number one Naomi Osaka raced through to the Round of 16 following a 6-3 6-2 triumph over American Katie Volynets. The Japanese star will now set her sights on Coco Gauff in what promises to be a massive fourth round battle.

A four-time Grand Slam winner who is still hitting her straps upon her return from giving birth to her child Shai, Osaka has shown glimpses of what she is capable of throughout the year, but is fit and firing as the WTA Tour enters its last two months of the season.

Against the 60th ranked Volynets, Osaka won 6-3 6-2 in an hour and 17 minutes to book her spot in the next round. It was the pair’s first ever meeting, with the 73rd ranked player able to break three times from eight chances without facing a break point opportunity herself.

At the same time, Osaka served five aces and won 82 and 68 per cent of her first and second serve points, and was able to win 50 per cent of her first serve return points to really put pressure on Volynets’ service game.

“For me, I wanted to keep growing from my last match,” Osaka said post-match. “I was just trying to be really aggressive from the beginning. … I felt like I really shouldn’t care too much about my unforced errors rather than just keeping her on the move.”

Looking ahead to her Round of 16 clash against world number six and fourth seed Gauff, Osaka said she was looking forward to the clash.

“I think it’s going to be a really cool test for me,” Osaka said “She’s played really well this year. … I’m excited to play the match, and I know people are excited to watch the match.”

It was a mixed bag for the American players on the day with Amanda Anisimova having a terrific upset over Russian Daria Kasatkina 7-6 6-4, while youngster Ashlyn Krueger bowed out in 74 minutes to top seed and world number two, Aryna Sabalenka. Seeded chance Madison Keys also overcame Brazilian Beatriz Haddad Maia 6-3 6-3.

In other results, local top ranked player Qinwen Zheng cruised past Argentinian Nadia Podoroska 6-3 6-2, while Poland’s Magda Linette stunned Italian Top 10 talent Jasmine Paolini 6-4 6-0 in a demolition job. Young Russian Mirra Andreeva knocked off Croatian Donna Vekic, while Spaniard Cristina Bucsa and Czech Karolina Muchova both stamped their tickets into the fourth round.