Russia’s Ekaterina Alexandrova has upset Wimbledon champion Simona Halep in the second round of the China Open, recording a 6-2 6-3 win for her first top-10 victory of the season.

Halep was troubled by the back injury that forced her to withdraw from last week’s Wuhan Open, dropping serve six times in the 63-minute encounter against her unseeded opponent.

“It was a pretty tough match but I think she didn’t play that well,” Alexandrova said. “I remember when we played last time in Cincinnati, it was tougher than today.

Halep showed no signs of the injury in her first-round straight-sets victory over qualifier Rebecca Peterson but admitted she now needed to take a break from the tour to fully recover.

“I didn’t recover well after my first match,” Halep said.

“So it was very tough for me to play and she played really well. The injury from Wuhan, it’s getting worse, so I have to go home and take an MRI… take a break and do some treatment.”

Bianca Andreescu survived a second-set onslaught from Aliaksandra Sasnovich to win her first match since her US Open triumph.

Her 6-2 2-6 6-1 victory over the Belarusian set up a third-round clash with Elise Mertens.

A poor service game from Andreescu, which included six double faults, gave Sasnovich 16 break points but the unseeded 25-year-old was able to convert only four.

Third seed Elina Svitolina won two tiebreaks to dispatch China’s Wang Yafan 7-6 (7-5) 7-6 (7-1) while Belinda Bencic battled back from a set down to beat veteran Venus Williams 3-6 6-3 7-5.

Defending champion Caroline Wozniacki sailed into the second round with a 6-1 6-3 win over American Lauren Davis.

World No.1 Ashleigh Barty is in action tomorrow when she takes on unseeded Kazakh Yulia Putintseva in the second round.

Australian No.2 Ajla Tomljanovic faces Alison Riske for a place in the last-16.