Thinking of fashion and tennis, one would be forgiven for assuming every athlete was a product-tester for Nike, Adidas, or Uniqlo. As the U.S. Open moves into the fourth round, with this era's tennis-greats moving up the bracket leaving those with a weaker or flawed style—both in play and look—packing and looking for the next flight out of Queens, Arthur Ashe Stadium is quickly becoming a premier runway and seriously agile advertisement for the sponsoring brands.

Serena Williams, who seeks to make history by winning a calendar year grand slam sweep with a victory at the Open, is not shy about her style credentials. Unlike most sponsored athletes at the Open, Serena's game is often talked about, at least in some circles, as much as her wardrobe on (and off) the court. Not to be outdone, Raphael Nadal was party recently to a very public game of "strip tennis," where he served off against several Tommy Hilfiger models, playing for points and losing some of the clothes off their backs in the process.

More than most other sporting events this year, the premium of seeing Serena potentially continue on her way to becoming the winningest tennis player in history makes the U.S. Open the hottest ticket in town. Yet, figure the considerable intrigue of style on the courts as well as that worn by the audience and the "hotness" of the Open takes another form. This year's tournament overlaps with New York Fashion Week, for instance. With a festival-like quality: a week and a half of events, celebrity entourages, travel to a distant place in the shape of Flushing Meadows, Queens, the sense of inclusion in something exclusive yet perennial, gives more reason to dress up.

Unlike other big American sporting events, fashion at the Open is distinct for several reasons. The history of tennis as a lawn game for the haute bourgeois of French and English origin begat the all-white and preppy look of the sport. It's influence, from Rene Lacoste to Fred Perry made the polo shirt look, a blend of sport and casual, a thing until Ralph took over the reigns. The uniforms for this year's Open staff and officials, as in previous years, is provided by Polo Ralph Lauren. So, the lure of wealth and a European sporting tradition attracts a sense of style that sees American athletic brands and an upscale setting colliding with New York tastes.

"The blurring of lines between sports and ready-to-wear via that hybrid known as athleisure wear has only exacerbated the situation," writes the New York Times. "Indeed, brands increasingly unveil their "collections" weeks in advance so consumers can Get the Look."

Tennis, it goes, is a game of love and tipping points. One in which Serena Williams may become a legend for what she does on the court. Her potential success at the Open could dramatically do for the game what Michael Jordan and Tiger Woods did for theirs. As for, say, Tomas Berdych, sixth seed and H&M's model-athlete, to a degree he'll probably be remembered for great play as well as for his gauche on-court style choices; the need to present a captivating personal image is crucial to tennis as a team-of-one sport. All this however, is emblematic of a particular combination of aggressive use of name brand designs and gear to bolster the retail and sports industries, already worth billions.