Serena Williams and Li Na were among the winners Sunday in the first round of the China Open.

The top-seeded Williams, who has already clinched the year-end No. 1 ranking, cruised past Russian Elena Vesnina, 6-4, 6-2, while the fourth-seeded Li handled Daniela Hantuchova of Slovakia, 6-0, 6-4.

Williams won this event in 2004 and is playing for the first time since capturing the U.S. Open earlier this month for her 17th career Grand Slam championship. She is gunning for her 10th title of 2013 and Sunday's win gave the American star an amazing match record of 77-4 for the year.

Li lost to Williams in the semifinals at Flushing Meadows and has not played since that 6-0, 6-3 setback. She won the season-opener in Shenzhen, but has not had much success at this event in her home country with semifinal losses in 2010 and 2012 her best results in eight previous appearances.

Third-seeded Agnieszka Radwanska, the 2011 Beijing champ, needed three sets to dispose of Switzerland's Stefanie Voegele, rallying for a 4-6, 6-4, 6-4 triumph.

One other seeded winner was Germany's Sabine Lisicki. The 13th-seeded Wimbledon runner-up posted a 6-3, 6-2 win over South Africa's Chanelle Scheepers. Lisicki will meet Venus Williams in the second round.

Czech veteran Lucie Safarova pulled off a 7-5, 6-3 win over former U.S. Open champ Samantha Stosur, this week's 15th seed.

Other winners Sunday included Americans Madison Keys and Lauren Davis, Russian Maria Kirilenko, Britain's Laura Robson, Japan's Misaki Doi and Estonia's Kaia Kanepi. Kirilenko, the 2005 Beijing winner, ousted Chinese wild card Zheng Jie, 7-5, 6-2.

First-round play will continue Monday with defending champion Victoria Azarenka set to meet Germany's Andrea Petkovic. Jelena Jankovic, the 2008 champ, will face Russian Anastasia Pavlyuchenkova and two-time winner Svetlana Kuznetsova will take on Taiwan's Su-Wei Hsieh.

The 2013 China Open titlist will collect $860,000.