Last week, Jonathan Isner voiced “disappointment” over US crowd support of his colorful French opponent, Gael Monfils. Rather than a failure of patriotism, the moment has been classed as a symptom of the contemporary game. The best players are foreign, the fanbases for all are global. While this is true, the roots of current fanaticism begin in a great American rivalry, one that extended beyond the court: Agassi vs. Sampras.

Tennis is built on personality. Clashing styles of play and the men behind them define generations. It is why we cheered (and jeered) McEnroe against less lippy opponents. And, why we reveled in the battles between Federer and Nadal—the only men to ever finish six consecutive calendar years at 1-2 in the rankings. It is also the reason that clashes between Agassi and Sampras had fans on the edge of their seats.

In 1995, Pete Sampras and Andre Agassi started the ATP season ranked one and two respectively. They ended the year in the same position. Andre defeated Pete in Australia. Pete bounced back and beat Andre in three sets at Indian Wells, only for Andre to reverse his fate a week later in Miami.

The rivalry was real. Top Americans, with competing styles of play, were trading titles. Serve and volley against the best returner in the game. Bada bing, bada boom.

Agassi reached the quarters in Paris, and headed into Wimbledon as the top seed. Though he faltered against Boris Becker in the semis, allowing Pete to defeat the German for a title on grass, Agassi cruised towards Flushing—taking titles in DC, Cincinnati, Montreal, and New Haven in the run-up. Sampras stayed quiet, reaching only one final (Montreal, where he lost to Agassi in three sets). One was boisterous, one quiet. One was a style icon, the other a pillar of practicality.

Sampras was still one year away from the shoe he's known for—the Tinker Hatfield designed Nike Air Oscillate—and his dress in 1995 was country club friendly. Madras-like shorts were matched with a clean white polo, with ribbing accents driven by the color of the bottoms. The most exciting element of the kit? The brilliant Nike tennis logo, a court with swoosh replacing the net.

In contrast, Agassi was setting new trends. His hair was close cropped. His shorts surfer long. His shoes, the brilliant Nike Air Challenge LWP, were paired (often) with black socks. The Agassi version of rock n' roll tennis was infused with some of basketball's Fab Five-born hip-hop swagger and muted tones that wouldn't have looked out of place in Seattle. At the US Open, the man wore black and copper plaid. Plaid! On a tennis court. Against Pete, he wore bold stripes. The microfiber shorts were tech grunge and anything but member club approved.

Coming into the US Open, Andre and Pete had played each other a total of 16 times. The contests were evenly split, and the juxtaposition of personality and tactic a natural fit for inventive marketing. In a John McEnroe-narrated clip, the two men played "Never Ending Tennis." Before the Open, they starred in a Spike Jonze-directed series of commercials titled "Guerrilla Tennis." They'd hop out of a yellow cab, toss a net in the street, and battle. It was sport for the sake of sport, no-holds-barred. The pinnacle of an early '90s drive to give tennis universal appeal and increased flare.

The title of the commercial drew from a CBS documentary on the pair that aired during the open. Highlights include: Agassi and Sampras ordering room service, Agassi doing his own laundry at an Alexandria, Virg. laundromat (while complaining that Nike had given him shirts that bleed), and the two guys generally showing more personality than tennis was know for. The program was not as dynamic as the matches, but it was revealing. Rivalry, true spirited American rivalry, had pushed tennis—fuck it, had pushed even the US Open—to an elevated stature.

Sampras defeated Agassi in four sets to take the 1995 US Open. It was a pivotal loss for Agassi, who'd eventually lose his grip on a rivalry Sampras dominated until his final win—the 2002 US Open final. Nothing would match the fervor of the summer of '95. It was a summer in which tennis and tennis style resonated off the court. It was a summer during which America reigned supreme (who even remembers Thomas Muster or Yevgeny Kafelnikov?) and held four of the top eight spots in the world. It was a summer that changed gave the game a contemporary look.

While watching the final weekend of the 2013 US Open, note the black shoes on court. Take a look at the socks. Remember the pioneers. Agassi and Sampras didn’t just ignite passion with their play. The two combined to change the look and feel of tennis, pushing beyond the pure personality-driven dance of the ‘80s, the rock-n-roll spirit of the early ‘90s, and driving an of-the-moment stake in the game. We can blame them for sleeveless shirts. Nadal’s atrocious capris. But, ultimately, we have to praise their rivalry for giving us the tennis we now know and love. A game that matches passion with fashion, pits individual flare against stodgy conservatism, and applauds the mental strength of the few great athletes who’ve figured out how to put it all together.

Nick Schonberger is Deputy Editor at Complex Media and a formerly a mediocre Water Polo player.

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