NEW YORK -- Once you reach a certain age, birthdays tend to make you reflect on your own mortality. They also, in the case of a professional athlete such as Andy Roddick, tend to prompt questions about the state of your career.
Roddick turned 28 on Monday, Day 1 of this year's U.S. Open, and after beating Stephane Robert of France 6-3, 6-2, 6-2, the ninth-seeded American was asked what significance he attributes to his age.
In typical Roddick fashion, he injected his reply with some humor.
"Obviously, I know I'm probably closer to the finish than I am to the start," he said. "But ... it's a number. I'm barely older than I was yesterday."
Well, yes, that's true. He also, however, is seven years older than he was when he won his lone Grand Slam title at the 2003 U.S. Open. There's a reminder of that accomplishment every time Roddick returns to Flushing Meadows: His spot in the locker room bears a special plate with his name and the year he was the champion, a bit of recognition he referred to as "the little deal on your locker that says you're special."
In women's action, 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."
Kim Clijsters, like Roddick, is "special," too. The Belgian won the U.S. Open each of the last two times she entered, in 2005 and 2009, and she stretched her winning streak in New York to 15 matches Monday despite a brief blip.
The No. 2-seeded Clijsters began her title defense with a 6-0, 7-5 victory over 104th-ranked Greta Arn of Hungary. It was an afternoon of mostly straightforward results, although two-time French Open runner-up Robin Soderling was stretched to five sets before edging 214th-ranked qualifier Andreas Haider-Maurer, who pounded 34 aces.
Other winners included No. 6 Nikolay Davydenko, No. 11 Marin Cilic, No. 13 Jurgen Melzer, No. 17 Gael Monfils and No. 22 Juan Carlos Ferrero, while No. 27 Fernando Gonzalez quit in the third set of his match against Ivan Dodig because of a knee injury.
Women moving into the second round included surprise 2009 U.S. Open quarterfinalist Melanie Oudin, French Open champion Francesca Schiavone, French Open runner-up Sam Stosur, two-time major finalist Elena Dementieva, No. 10 Victoria Azarenka, No. 13 Marion Bartoli, No. 16 Shahar Peer, and No. 24 Daniela Hantuchova, who beat former No. 1 Dinara Safina 6-3, 6-4.
Venus Williams, a two-time champion in New York, and Roger Federer, who counts five U.S. Opens among his record 16 Grand Slam titles, were scheduled to play in the night session.
After rolling through the first set against Arn, Clijsters trailed 4-0 in the second. Arn eventually served for that set at 5-4. But Clijsters broke serve there, and again in the match's final game.
As for how she found herself in that hole to begin the second set, Clijsters explained: "Wasn't aggressive enough. Didn't step in enough when I had to. I think she started going for a little bit more, playing a little bit more with some risks, and she kind of put me under pressure a little bit, where it should have been the other way around."
At last year's U.S. Open, Clijsters became the first wild-card entrant to win a women's singles title at any Grand Slam tournament. Coming off a 21/2-year break from the game, during which she got married and had a baby, Clijsters was playing in only her third tournament of her comeback, and first major event.
"Other players kind of didn't really know what to expect," Clijsters said.
That isn't going to be the case these days for her, of course. Nor can Oudin catch anyone off guard anymore.
A year ago, Oudin was only 17. She came to New York ranked 70th, and without a U.S. Open win on her resume.
"I've grown up a lot," Oudin said after reeling off the last nine games in a 6-3, 6-0 victory over 143rd-ranked Olga Savchuk.