Simona Halep defeated Maria Sharapova for the first time in her career, romping to a 6-2 6-2 win over the Russian in round three of the China Open.
Sharapova had won all seven of their previous meetings, including a hard-fought clash at the US Open this year.
However, the 30-year-old five-time Grand Slam winner has been inconsistent since her return from a 15-month suspension for taking the banned substance meldonium.
And she was no match for Halep as the world No 2 produced a relentless display, featuring power-packed ground strokes, gallant defence and hardly any unforced errors.
"It was a great match, I think I played my best tennis against her. I served pretty well, and the work that I did after the US Open, I could see it on court today," Halep said on the official WTA website.
"I'm really happy that I could do this. It's my first victory against her and I just want to enjoy the moment."
Two victories this week will see Sharapova climb back into the top 100 for the first time since her doping ban, and she gave full credit to Halep.
The 30-year-old said: "I think she played an incredible match, probably the best she's played against me in all of our previous meetings. I wasn't as sharp. I wasn't seeing the ball as well. I wasn't moving up and down as well as I have been against her."
With World No 1 Garbine Muguriza having already exited the tournament, Halep appears to be a leading contender to go on and claim the title in the Chinese capital.
The Romanian will next take on Russia's Daria Kasatkina, who upset defending champion Agnieszka Radwanska 4-6 7-5 6-2.
French Open champion Jelena Ostapenko of Latvia became the seventh player to qualify for the season-ending WTA Finals in Singapore with a 6-3 7-5 win over Australia's Samantha Stosur in round two.
Also advancing to the third round were China's Peng Shuai, who made short work of Romanian Monica Niculescu with a 6-3 6-2 win, and Wuhan Open champion Caroline Garcia of France, who overcame Belgian Elise Mertens 7-6 (7-4) 6-4.
Ukrainian Elina Svitolina defeated Australia's Ashleigh Barty 6-4 6-2 in the second round to set up a clash with Russia's Elena Vesnina.
Sky Sports Tennis will have all the action from the ATP China Open, Japan Open and Shanghai Masters before the action heads to Paris.
The Next Gen ATP Finals in Milan and season-ending extravaganza World Tour Finals at London's O2 in November end another memorable year which will covered via our website sky.mnosports.com/tennis with live blogs and updates as the season reaches its climax.
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