NEW YORK - In one breath, Serena Williams says she considers herself the favorite at the U.S. Open.

In the next, she says she doesn't want to be touted as the woman to beat at the year's last Grand Slam tournament, which begins Monday.

At one point, Williams says she has no target number for major titles. At another point, she says she really was hoping to surpass Monica Seles' nine major singles championships — and now that Williams has 11, she wants to catch Billie Jean King's career count of 12.

"I used to never look at numbers. But the more I get, the more numbers I look at," Williams said in an interview with The Associated Press. "I want to get back to where I don't look at numbers."

Perhaps Williams is simply saying the first thing that comes to mind. Perhaps she's really not sure how she feels. Or perhaps she's working on her acting chops during interviews and news conferences.

This much is clear: There have been two very different tennis players who have shown up under the name "Serena Williams" the past 12 months.

Check out these statistics dating to the start of the 2008 U.S. Open:

• Grand Slam Tournament Serena Williams is 25-1, for a .962 winning percentage, with three titles at the past four major championships, including a year ago at Flushing Meadows; she is 9-1 against top-10 players at majors in that span.
• Lesser Tournament Serena Williams is 21-11 (plus one walkover), for a .656 winning percentage, with zero titles at her past 12 nonmajor events; she is 3-5 against top-10 players at nonmajors in that span.

The contrast in numbers is far less pronounced for older sister Venus, but she, too, tends to play her best on the sport's biggest stages. Venus ranks second to Serena among active women with seven major titles.

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"The Williams sisters just take it to another level when they are playing the Slams," observed Martina Navratilova, who won 18 Grand Slam singles titles.

"The Williams sisters look at it as an opportunity," added Navratilova, part of Tennis Channel's announcing team at the U.S. Open. "They don't put that much pressure on themselves when they play the other tournaments. It's sort of like warmups."

Compare that to someone such as Dinara Safina, who is No. 1 in the WTA rankings and seeded No. 1 at the U.S. Open, ahead of No. 2 Serena Williams and No. 3 Venus Williams. Safina is 0-3 in Grand Slam finals over her career; she has, however, won three other titles in 2009.

Ask the younger Williams about the key to defending her championship at Flushing Meadows and she insists that she can't allow any shred of pressure to creep into her thoughts.

"I have to be really relaxed. Last year, I was super relaxed, and super calm. I just enjoyed every moment," she said. "That's where I need to be again."

Williams certainly knows what it takes to succeed at major tournaments, but there have been dips in performance at those events, too. For a while, she drew criticism for spending too much time pursuing outside interests and not enough time honing her game.

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On the other hand, Williams' forays into fashion and acting helped turn her into something of a brand. She is not merely a sports star; she is a celebrity.

That's why she was invited to unveil a wax figure of herself Thursday at Madame Tussauds New York. That's why she was asked to make a guest appearance on Shaquille O'Neal's reality TV show. That's why she has an autobiography coming out next week. That's why she has nearly 1 million followers on Twitter.

That said, Williams is at her best — and is as good as it gets — when she has a racket in her hand, particularly at Grand Slam tournaments these days.

"I'm happy where I'm at, and I feel like I have several hundred more years to play," said Williams, who turns 28 in September. "Hopefully I'll win more."

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