Stephens adds to breakout year by upsetting Schiavone at U.S. Open

But there's no mistaking her role as the sport's Next Big Thing at this year's tournament. Stephens' image is plastered all over the event, from the American Express posters hanging liberally around the grounds to the oversized banners along the boardwalk that connects the 7 train subway stop to the Billie Jean King National Tennis Center.

The idolatry is not without merit. It's been a breakthrough year for the 19-year-old from Plantation, Fla., who made the second round at the Australian Open, the third round at Wimbledon, and became the first American teenager to reach the last 16 at the French Open since Serena Williams more than a decade ago.

Yet progress is seldom a straight line. Fact is, it would have been forgivable, if disappointing, if Stephens had succumbed to a sophomore slump in Tuesday's first-round match against Francesca Schiavone, the 22nd-seeded Italian whose previous two seasons have included a Grand Slam title and a lengthy stint in the top 10. Just ask Melanie Oudin about the pressure that an auspicious Gotham debut can breed.

Yet Stephens, now the youngest player in the top 50, wasn't ready for her charmed season to end.

"It's time," was Stephens' self-described reaction upon hearing the draw. "It's either go big or go home."

On Tuesday, Stephens opted for the former, delivering a tactically superb performance to secure a 6-3, 6-4 victory, outmuscling and outwitting an opponent who's always relied more on imagination and guile than horsepower. As the sun disappeared over the western end of Louis Armstrong Stadium, Stephens fought through fatigue -- and Schiavone's famed siege mentality -- showing an improved focus and intensity to finish off the upset in straight sets.

The 32-year-old Schiavone showed flashes of the sublime shotmaking that lifted her to a memorable late-career peak, but such moments come fewer and farther between for the stylish Italian these days -- and Stephens was more than capable of filling in the negative space. The American hammered booming serves (topping out at 123 m.p.h.) and powerful, angled groundstrokes that confounded Schiavone, the occasional drop shot demonstrating Stephens' matured variety and command of point construction.

Yet it's Stephens' ebullient personality that continues to win popular favor as much as her bold promise and crowd-pleasing style. When asked how she felt about the additional publicity, Stephens' unhesitant, unrepentant response evoked the quick first step that she'd used to put away so many Schiavone short balls.

"I just think it's so cool," Stephens gushed, without an ounce of artifice. "Everyone who walks by, I'm sure they're like, 'That's awesome, that's cool.' I love myself. Seeing myself is unbelievable. I don't know if you feel that way, but when I see myself I like freak out."

Now a winnable match with German qualifier Tatjana Malek awaits in Thursday's second round, with the opportunity to advance in a section of the draw thrown into disarray by Caroline Wozniacki's abrupt first-round exit.

"Amazing experiences," Stephens reflected. "This year has been unbelievable. And it's been so much fun. Everything I've gone through this year, the really terrible things and the really good things, I've learned so much that I'm like, wow, 2012 has been pretty good to me."

And better still can be.