Coco Vandeweghe has sealed a place in the third round of the Wuhan Open without winning a set after Jelena Jankovic was forced to retire.
Jankovic suffered a break in her opening service game of the first set as Vandeweghe stormed to a swift 4-1 lead on the hard court.
It shortly became clear that the 10th seed couldn't continue and she withdrew from the match after putting just one game on the board.
American Vandeweghe will play Caroline Garcia, who knocked out Agnieszka Radwanska, in the next round.
