NEW YORK (AP) – Defending champion Kim Clijsters briefly lost her step on a windy day before recovering in time to win her 15th straight match at the US Open.

The second-seeded Belgian beat Hungary's Greta Arn 6-0, 7-5 in the first round yesterday.

She fell behind 4-0 in the second set, and the 104th-ranked Arn had a chance to serve out the set at 5-4. But Clijsters got the break, then did it again to clinch the straight-set victory.

Clijsters said she wasn't aggressive enough playing with the wind at her back early in the second set, waiting for the ball instead of moving up for it.

"She kind of put me under pressure a little bit where it should have been the other way around," she said.

A year ago, Clijsters was a wild-card entry in only her third tournament back after two and a half years away from the sport. Now she's one of the favourites to win the Open.

Melanie Oudin and Francesca Schiavone also know how quickly perceptions can change.

Oudin has struggled with higher expectations since her crowd-pleasing run to the US Open quarterfinals last year. So has Schiavone after her breakthrough French Open title in June.

But neither showed any signs of the pressure in cruising to dominant first-round wins.

Oudin, the 18-year-old from Marietta, Georgia, needed just 56 minutes to beat Olga Savchuk of Ukraine 6-3, 6-0.

Schiavone, the Italian who won her first Grand Slam weeks before her 30th birthday, dispatched Ayumi Morita of Japan 6-1, 6-0 in 58 minutes.

If anything, Schiavone seems to be having fun in the spotlight. Asked why she's a fan favourite, she playfully replied, "I attract them because I'm beautiful."

Schiavone acknowledged that maybe she's a bit more motivated at a Grand Slam than at other tournaments. Schiavone, seeded six, had been just 3-6 since winning at Roland Garros. She lost in the first round at Wimbledon and dropped her opening match at three other tournaments.

She was pleased that her first-round match was in the grandstand – a year ago, she was relegated to an outer court.

"I like to do it, because adrenaline is coming up and I enjoy much more than play in faraway court," she said with a laugh. "Maybe because I am 30 years old and now I want to enjoy with people."

Fifth-seeded Sam Stosur of Australia, who lost to Schiavone in the French final, dropped her first set yesterday before rallying to beat Elena Vesnina of Russia 3-6, 7-6 (2), 6-1.

The ninth-seeded Roddick celebrated his 28th birthday by beating Stephane Robert of France 6-3, 6-2, 6-2.

Two-time French Open runner-up Robin Soderling was pushed to five sets by a qualifier ranked 214th in the world. The numbr five-seeded Swede beat Andreas Haider-Maurer of Austria 7-5, 6-3, 6-7 (2), 5-7, 6-4.

No. 24 seed Daniela Hantuchova beat former world nuber one1 Dinara Safina 6-3, 6-4. The unseeded Safina missed almost three months this year with a back injury and has slipped to 50th in the world rankings. She was the top seed at last year's US Open, but lost in the third round. Number 12 seed Elena Dementieva, 13 Marion Bartoli and 16 Shahar Peer also won.

Russia's Nikolay Davydenko, the men' sixth seed, beat American Michael Russell 6-4, 6-1, 6-3. Number 11 Marin Cilic, 13 Jurgen Melzer and 22 Juan Carlos Ferrero also advanced. Number 27 Fernando Gonzalez of Chile retired against Ivan Dodig of Croatia.