Maria Sharapova’s latest little black dress may look bound for a red carpet event. Instead, the statuesque blonde will don the glamorous number on the hard court at the U.S. Open — the two-week tennis tournament that began yesterday in Queens.

Designed for Ms. Sharapova, the 19-year-old 2004 Wimbledon champion, the Nike outfit boasts an empire waist, a ribbon accent, and boat-cut neckline adorned with Swarovski crystals, a Nike spokesman, KeJuan Wilkins, said. “This dress has a lot of runway inspiration behind it,” he said. “Maria is regarded as someone who is both elegant and fierce, and we feel that the dress reflects that.”

The Russian tennis star chose a form-fitting, lavender-and-black tank dress for daytime play.

A far cry from the demure white ensembles of Wimbledon, the U.S. Open is a veritable “on-court runway show,” a sportswear buyer at Mason’s Tennis Shop on East 53rd Street, Dana Mason, said.

Thank the style-conscious Williams sisters and the eccentric fashions of Bethanie Mattek for the transformation of women’s tennis uniforms. On-court looks have gone from pleated skirts and polo shirts to bold colors, patterns, and cuts that appear more suited for the catwalk or, perhaps, a rave. Think Serena Williams’ jean skirt and kneehigh lace-ups, or Ms. Mattek’s leopard-print ensemble, both at the 2004 U.S. Open.

“Dresses have gotten shorter over the years,” Ms. Mason said. “The colors have gotten brighter, and the styles have become more girly, more feminine.” As of yesterday, a black dress identical to the one Ms. Sharapova will wear at the U.S. Open was on display at Mason’s, but is not on sale.

Ms. Sharapova may be the Carolyn Bessette of tennis, with her elegant, tailored style and long blonde ponytail, but she will not be the only tennis star flaunting her fashion flair at Flushing Meadows this year.

Maria Kirilenko, 19, will hit the court in apparel designed by Stella McCartney for Adidas.The Russian tennis star’s U.S. Open wardrobe comprises a whimsical white sleeveless dress with a peasant-style skirt, and an unevenly cut miniskirt in seafoam green, paired with a formfitting white tank, an Adidas spokeswoman, Dorothee Kurz, said.

Younger top-ranked players, such as Ms. Kirilenko and 18-year-old Ana Ivanovic, are sporting envelope-pushing tennis wear that Ms. Kurz describes as “the perfect combination of fashion and sports performance.”

Ms. Ivanovic, who is Serbian, is slated to debut in a short, black wrap-style skirt, and hip-length white top, with spaghetti-straps and a plunging neckline, Ms. Kurz said.

In addition to evening wear-inspired looks — Kim Clijsters planned to wear a black dress by Fila until a wrist injury forced her to withdraw from the competition — U.S. Open fashion trends include unabashedly feminine pieces and jewel-toned ensembles, stylists said.

This year’s Wimbledon and Australian Open champion, Amélie Mauresmo, will make her U.S. Open debut in Rbk’s Match Day tank and skirt in “tiger orange.” The French champion will also sport matching navy and orange Match Point sneakers, according to Reebok’s global director of tennis, Dianne Hayes.

Rbk Match Day is also dressing 17-year-old Nicole Vaidisova, who will wear a decidedly more feminine frosted blue dress with a “flirty pleat look,” Ms. Hayes said.

Advances in lightweight and breathable fabrics — Nike’s “Dry-Fit” and Adidas’ “ClimaCool,” for example — mean these new envelope-pushing designs are as utilitarian as they are stylish, the executive editor of Style.com, Nicole Phelps, said.”It’s not runway to reality; it’s runway to clay court,”she said.

She said sportswear sponsors are increasingly willing to go to great lengths to ensure their players are happy with their on-court wardrobe. “Tennis pros are real stars now — like in Hollywood,” Ms. Phelps said. “Of course they’re signed with some of the biggest sports companies, which want to retain them, and to make these deals attractive to them.”

While the bolder designs may make heads spin — and headlines — some topranked women prefer more traditional tennis apparel, according to Ms. Kurz of Adidas. She said Justine Henin-Hardenne, 24, generally prefers to wear shirtsleeves, though she has also requested a sleeveless option for her modest turquoise-and-black ensemble. “She’s a true and authentic athlete, and this fits with her personality,” she said.

U.S. Open fashions — of the eye-popping and more conservative varieties — are making bigger ripples in the retail market, Ms. Mason, of Mason’s Tennis Shop, said. “Dresses, like those worn by the players, can cost $90, but people will pay for it without thinking twice,” she said. “Little girls, especially, they want to look like their idols.”