(Photo credit: Robert Deutsch-USA TODAY Sports)

No. 2 seed Iga Swiatek of Poland and U.S. Open champion Coco Gauff both won their China Open debuts in straight sets on Monday in Beijing.

Swiatek advanced to the second round of the WTA 1000 tournament with a 6-4, 6-3 victory over Sara Sorribes Tormo of Spain. Her next opponent will be France's Varvara Gracheva.

Swiatek fired 17 winners and won 15 of 17 net points in the first set. She then won 12 of the first 14 points in the second set to open up a 3-0 lead, finishing the match with 27 winners to 25 unforced errors. Swiatek broke Sorribes Tormo's serve seven times.

"For sure, today I felt really confident and comfortable because I've been practicing that a lot," Swiatek said. "I'm pretty proud of my performance at the net because, technically, I feel like my volley has changed. I'm really happy with that.

"I think against some players it's kind of necessary to go to the net, and today that was that kind of a match."

The third-seeded Gauff extended her winning streak to 13 matches by defeating Russia's Ekaterina Alexandrova 7-5, 6-3 in 1 hour and 22 minutes. The 19-year-old Gauff has won 19 of 20 matches since her first-round setback at Wimbledon.

Gauff converted four of her eight break chances and finished with 11 winners and 11 unforced errors, compared to 19 winners and 24 unforced errors for the 20th-ranked Alexandrova. Serving at 5-6 in the opening set, Alexandrova shot herself in the foot with two double faults and a backhand into the net.

"Overall I'm happy with how I was able to push through," Gauff said. "Is it how I like to play? Probably not. But I knew coming in was going to be tough, just coming from across the world. This is the first time here. I knew it was going to be a tough match for me regardless. Especially Alexandrova, she's a great player. I'm happy with how I was able to manage."

Gauff's second-round opponent will be Croatia's Petra Martic.

No. 5 seed Elena Rybakina of Kazakhstan breezed to a 6-1, 6-2 first-round win over China's Qinwen Zheng. No. 7 Ons Jabeur of Tunisia also advanced to the second round with a 6-3, 6-4 win over Ashlyn Krueger. No. 9 Caroline Garcia of France was a 6-2, 6-4 winner against Ukraine's Kateryna Baindl.

No. 11 Daria Kasatkina of Russia outlasted Egypt's Mayar Sherif 1-6, 6-4, 7-6 (8), while Russia's Liudmila Samsonova knocked out No. 12 Petra Kvitova of the Czech Republic 6-4, 7-5.