Venus Williams landed awkwardly on her recently injured leg after hitting a swinging volley and grimaced. It was about the only glitch during her return to tennis.
Playing for the first time in two months after spraining her left kneecap, seven-time Grand Slam champion Williams beat Roberta Vinci of Italy 6-4, 6-1 Monday night to reach the U.S. Open's second round.
"It was doing pretty good, till I landed on that leg on the swing volley. ... I was pretty happy to get through after not playing in forever," said Williams, whose younger sister Serena isn't playing in the U.S. Open after surgery for deep cuts on her right foot.
"It's not the same without two Williamses," the No. 3-seeded Venus added during an on-court interview. "I have big shoes to fill with just one Williams here."
She hit 10 aces, reaching 126 mph, and became only the fifth woman with 200 career victories at major tournaments.
Vinci knew, of course, about Williams' recent time off, and said afterward with a sigh: "I hoped she would play worse."
Two of the American's seven Grand Slam titles came at Flushing Meadows, in 2000 and 2001, and other past U.S. Open champions Kim Clijsters, Andy Roddick and Roger Federer also won on Day 1. But 32nd-seeded Lleyton Hewitt, who won the tournament in 2001, hit 12 double-faults and was upset by 109th-ranked Paul-Henri Mathieu of France 6-3, 6-4, 5-7, 4-6, 6-1.
"I wasn't expecting a whole heap coming into this tournament, based on my preparation," said Hewitt, who had played only four matches, losing three, since Wimbledon.
Monday's loss is Hewitt's only first-round exit in 11 trips to the U.S. Open. Williams, meanwhile, improved to 12-0 in opening matches in New York, and 48-3 in openers at all major tournaments.
She hadn't competed since being upset in the Wimbledon quarterfinals June 29 by then-No. 82 Tsvetana Pironkova of Bulgaria. Pironkova won Monday, too, and Williams could face her in the third round.
Roddick turned 28 on Monday, and beat Stephane Robert of France 6-3, 6-2, 6-2. Federer beat Brian Dabul of Argentina 6-1, 6-4, 6-2.
The No. 2-seeded Clijsters began her title defense with a 6-0, 7-5 victory against 104th-ranked Greta Arn of Hungary.