They played loose and fearless, simply because they had nothing to lose. A No. 16 seed had never beaten a No. 1 seed in the N.C.A.A. men’s basketball tournament. Who would ever think that the tiny University of Maryland-Baltimore County would be the ones to break through?

Certainly not against Virginia, the top overall seed, a two-loss team that had handily won the nation’s toughest league — the Atlantic Coast Conference — and its conference tournament.

But the N.C.A.A. tournament is different. The Cavaliers carried all the pressure; the Retrievers none of it. And they rode that carefree wave of insouciance to what might have to be considered the greatest upset in college basketball history.

This one was for Princeton, East Tennessee State, Western Carolina — all the No. 16 seeds that had come close to upsets as the biggest underdogs on the biggest stage. Since 1985, No. 1 seeds had advanced at least to the second round 135 consecutive times. Virginia, playing only a few hours from home, would become the first to fail, 74-54, at the Spectrum Center in Charlotte.