KATIE BOULTER was knocked out of the China Open following a straight-sets defeat to Coco Gauff in the third round.

A battling performance saw Boulter test the world number six, but Gauff managed to snatch a tight first set before wrapping up victory in the second to win 7-5 6-2.

Gauff will now face either Naomi Osaka or Katie Volynets in the last 16.