Updated

Top seed Victoria Azarenka, reigning champion Samantha Stosur and three-time titlist Kim Clijsters were first-round winners on Day 1 at the 2012 U.S. Open.

The Belarusian Azarenka hardly broke a sweat in her opening match against Alexandra Panova, dropping one game to the Russian. Panova recorded only two winners in the 6-0, 6-1 thrashing at Louis Armstrong Stadium.

The seventh-seeded Stosur won her eighth straight match in New York with a brisk 51-minute 6-1, 6-1 pasting of Croat Petra Martic at Arthur Ashe Stadium. Stosur won the first 19 points of the match and fired 10 aces past a helpless Martic. The Aussie lost only four points while serving in the lopsided affair.

Stosur stunned American great Serena Williams in last year's U.S. Open finale to capture her lone career Grand Slam title. The Aussie star was also a French Open runner-up in 2010.

"As soon as I got here, it was just a good feeling and excitement to be back to a city that obviously brought me so much last year," Stosur said.

The 28-year-old Stosur, who has been somewhat disappointing this year, was a first-round loser at the Australian Open in January and Olympic Games last month and lost in the second round at Wimbledon in June.

Clijsters extended her winning streak at Flushing Meadows to 22 matches with a 6-3, 6-1 triumph over 16-year-old American Victoria Duval, the youngest player in the draw.

The 23rd-seeded Belgian, who is participating in the final tournament of her career, won back-to-back U.S. Open titles in 2009-10, but she couldn't contend for a three-peat last year, missing the fortnight with an abdominal injury.

Third-seeded Russian Maria Sharapova, meanwhile, breezed past Hungarian Melinda Czink 6-2, 6-2. The 2006 U.S. Open champ, Sharapova completed the career Grand Slam earlier this year by winning at Roland Garros.

Czech Petra Kvitova, fresh off capturing a title at New Haven this past weekend, rebounded from a slow start to post a 7-6 (8-6), 6-1 victory over Slovenia's Polona Hercog. The fifth-seeded Kvitova is this year's U.S. Open series champion, meaning she'll earn a $1 million bonus for winning the final major of 2012.

Ninth-seeded former French Open champ Li Na of China advanced following a more-than-two-hour rain delay with a 6-2, 6-3 handling of Britain's Heather Watson, while 11th-seeded former Wimbledon runner-up Marion Bartoli of France won her 18th straight first-round Grand Slam match by topping American Jamie Hampton 6-3, 7-6 (7-5). Na was a hardcourt titlist in Cincinnati two weeks ago.

In other action involving seeds, No. 15 Czech Lucie Safarova handled American Melanie Oudin 6-4, 6-0, No. 17 Russian Anastasia Pavlyuchenkova bested Slovakian Daniela Hantuchova 6-4, 7-6 (7-1), No. 19 Russian Nadia Petrova beat Aussie Jarmila Gajdosova 6-3, 7-6 (7-3), No. 25 Belgian Yanina Wickmayer topped Julia Glushko of Israel 7-5, 6-2, and No. 31 American Varvara Lepchenko outlasted Frenchwoman Mathilde Johansson 6-3, 3-6, 7-5.

Chinese Zheng Jie, seeded 28th, dropped the first set against Virginie Razzano, but battled back to take the second before the Frenchwoman retired.

Upsets came when Romanian Sorana Cirstea overcame 16th-seeded German Sabine Lisicki 4-6, 6-2, 6-2, Czech Kristyna Pliskova dismissed 18th-seeded German Julia Goerges 7-6 (7-4), 6-1, and Czech Lucie Hradecka doused 27th-seeded Spaniard Anabel Medina Garrigues 6-3, 6-3.

Also advancing were Romanian Simona Halep, Aussie Casey Dellacqua, Georgian Anna Tatishvili, Frenchwoman Kristina Mladenovic, Luxembourg's Mandy Minella, Swiss Romina Oprandi, Spaniard Lourdes Dominguez Lino, American Mallory Burdette, Frenchwoman Pauline Parmentier, Romanian Edina Gallovits-Hall, Australian Anastasia Rodionova, Brit Laura Robson, France's Alize Cornet, Belgian Kirsten Flipkens, Slovakian Magdalena Rybarikova and Canadian Aleksandra Wozniak.