The second-seeded American reached her first semifinal since the French Open in June.

Coco Gauff put down a spirited challenge from 66th-ranked Eva Lys to earn a 6-3 6-4 victory in Beijing on Thursday and reach the China Open semifinals for a second successive year.

Gauff, who is bidding to become the first woman to win back-to-back titles at the WTA 1000 event, had battled through three-setters in the previous two rounds and had to overcome stiff resistance from the German.

“I’m happy with how I played today. She’s a tough opponent, she hit a couple of great shots on the run,” Gauff said.

“I think I need to stay confident in my game and not be too passive when I have the lead. I played one passive point in this match, but otherwise I played well.”

It was a fast and furious start to the first set as both players fired off a string of winners and traded early breaks as the momentum swung wildly.

Following a run of five straight breaks of serve it was defending champion Gauff who finally seized control, taking a 5-3 lead when Lys sent a backhand wide and then consolidating to clinch the first set.

The world number three appeared to have found her range on serve in the second set and eased through a couple of holds, but a brief wobble and a few double-faults from the American added some late drama.

Serving for the match at 5-4, however, Gauff held her nerve to close out the win in an hour and 28 minutes.

The two-time Grand Slam champion next faces either compatriot Amanda Anisimova or Italian Jasmine Paolini, who meet in the second quarterfinal on Thursday.