MASON, OH - AUGUST 16: Ashleigh Barty of Australia returns a shot to Venus Williams during Day 5 of the Western & Southern Open at the Linder Family Tennis Center on August 16, 2017 in Mason, Ohio. (Photo by Rob Carr/Getty Images)

Australian Ash Barty could not follow up her shock victory over world No.9 Venus Williams at the Cincinnati Open, going down to Dane Caroline Wozniacki in straight sets in the round of 16 overnight.

Wozniacki cruised past the 21-year-old Aussie, 6-4, 6-2, on her way to the quarter-finals, where she will face either world No.1 Karolina Pliskova or Italian Camila Giorgi.

Despite the loss, Barty will become Australian's second highest ranked female player, behind Daria Gavrilova, overtaking fellow Queenslander, Sam Stosur, who is currently sidelined with a wrist injury.

Barty's win over Venus Williams last round, saw her reach world No.42, while Stosur has dropped two placed, to No.44 in the world.