LONDON, June 10 (Xinhua) -- China's Zheng Saisai beat British No.1 Johanna Konta 6-4, 7-5 in the second round of the WTA Nottingham tournament on Thursday, upsetting the British favorite's joy at breaking into the world's top 20.
Zheng fought back from 2-0 down in the opening set with two breaks of serve and took it in 45 minutes.
Second seed Konta was on course to level the match when she went 4-2 up in the second set, only to relinquish her advantage afterwards and was consigned to defeat.
Konta underwent treatment during the match when she felt uncomfortable in her lower back.
"She played a lot of balls and got a lot of balls back. I think there were a lot of high-quality points," Konta said.
Zheng will encounter Tara Moore in the quarter-finals following the Briton's 6-2, 6-2 defeat of eighth seed Christina McHale.