Kim Clijsters kicked off her US Open title defence with a straight-sets win over world No.104 Greta Arn - but it didn't all go to plan for the Belgian.
It looked like Arn wouldn't last long against the second seed as Clijsters raced through the first set 6-0 in just 18 minutes.
But the Hungarian wouldn't lie down and capitalised on a lapse in concentration from Clijsters to jump to a 4-0 lead in the second set.
As expected, however, the defending champion rallied and reeled off two quick breaks of serve to claw her way back into the set.
She took the lead at 6-5 and then broke Arn's serve for the sixth time in the match to seal her 6-0 7-5 victory.
Clijsters will now meet Australian Sally Peers in the second round after the teenager pulled off a remarkable 6-0 6-1 win over Canada's Aleksandra Wozniak.
This is 19-year-old Peers' first time playing in the main draw at Flushing Meadows after winning her way through qualifying at the weekend.
But she showed no signs of nerves, ruthlessly disposing of Wozniack in just 48 minutes, with the Canadian failing to hold serve once during the match.
Sixth seed Francesca Schiavone scored a comfortable 6-1 6-0 win over Japan's Ayumi Morita.
The French Open champion claimed victory in just under an hour to set up a second-round clash with compatriot Maria Elena Camerin, who beat Australian Sophie Ferguson 6-4 6-0.
Elena Dementieva, the No.12 seed, also cruised into the second round with a 6-1 6-2 defeat of Belarus' Olga Govortsova, while 29th seed Alona Bondarenko needed three sets to get past Russia's Vera Dushevina before eventually winning through 6-0 5-7 6-4.
Other seeds to make it through to the second round so far on day one are 28th seed Alisa Kleybanova of Russia, who beat Swede Johanna Larssson 7-6 6-2, and 20th seed Anastasia Pavlyuchenkova, who defeated Germany's Kristina Barrois 6-4 6-1.