This year, as we celebrate the 50th anniversary of the US Open, we’re counting down the 50 most memorable moments in the history of America’s Grand Slam. Today, we take a look back at No. 33.

He came out of California, displaying gifts few players possessed, playing the game with ineffable grace and immense power, serving his way effortlessly through arduous afternoons against obstinate opponents. Insiders knew full well that he was a rare talent, a champion in the making and a young fellow with high aspirations.

And yet Pete Sampras was still a work in progress when he arrived for the 1990 US Open. He was seeded 12th after an impressive but uneven season. Few in the know gave him much of a chance to win the last major of that season; in seven previous majors, he had not yet gone beyond the fourth round, although he had upended defending champion Mats Wilander at the 1989 US Open.

Now, in the new decade, totally against the odds, Sampras got on an astounding roll. In the round of 16, he came from behind to defeat the indefatigable Austrian left-hander Thomas Muster in four sets. One round later, he brought down Ivan Lendl in a five-set thriller, and that was no mean feat. Lendl had been in a record eight consecutive finals from 1982-89 and had secured the title three times. In the penultimate round, Sampras knocked out four-time Open victor John McEnroe in four.

play video 50 Moments That Mattered: Sampras comes of age at 19

That set the stage for a final-round duel with the heavily favored Andre Agassi, the No. 4 seed. By this time, Sampras was playing an unconsciously brilliant brand of tennis. He blew his compatriot off the court, 6-4, 6-3, 6-2, with an awesome performance. In 13 service games against one of the great return-of-serve artists of all time, Sampras allowed Agassi only 17 points. Moreover, Sampras sprinkled the court liberally with outright winners, on the volley, off the ground and often from improbable positions. It was a virtuoso performance from start to finish. Agassi never had a chance to subdue a soaring rival.

Sampras established himself as the youngest man ever to take the title, at 19 years and 28 days old. He would reflect many years later, “The Open is where I made my mark. I got hot at the right time and played some of the best tennis of my career at a time when I had nothing to lose. It was like a fairy tale, and I didn’t quite know the impact I was going to have on the game.”

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