UNC Greensboro had completed its comeback. Or so it seemed.

The 13th-seeded Spartans, ignored by almost every expert in the never-ending search for March Madness upset picks, had come all the way back from 12 points down in the second half of their first-round game against Gonzaga. And with under two minutes to play, they had finally taken a lead.

Then the upset bid went awry in agonizing fashion.

Greensboro had so many chances to close the deal. And even after turnovers and a clutch Gonzaga shot put the Spartans in a three-point hole with less than 20 seconds to play, senior guard Marvin Smith rose and fired for the tie. His 3-point shot, almost literally, was in the basket.

And then it wasn’t. It rimmed out:

And Gonzaga, on the back of a cold-blooded, tie-breaking 3-pointer from freshman guard Zach Norvell Jr., survived.

But the story of the dramatic finish was what allowed Norvell to put Gonzaga back up three, and what allowed it to stand as the game-winner.

Greensboro’s comeback had been furious. Its vexing defense confounded the Zags over the final nine minutes. And as Gonzaga’s offense stalled – in part thanks to 12 missed free throws – Francis Alonso, Jordy Kuiper and Demetrius Troy brought the Southern Conference champions back into the game.

But countless mistakes – some minuscule, some major – ultimately cost them. There were fumbled rebounds, and a foot on the line that turned a 3 into a 2.

Kuiper’s put-back gave Greensboro its first lead since early in the first half, 64-62, with 1:46 to go. With just over a minute to go, the Spartans had a chance to extend that lead. But an ill-advised and errant alley-oop pass gave the ball back to Gonzaga.

Josh Perkins tied the game at 64 with 51 seconds to go, but even then, the underdogs had a chance to re-gain control. Instead, they threw that chance away. Alonso hit the side of the backboard with a forced runner.

After Norvell’s shot, Alonso pushed off on Silas Melson, and was called for an offensive foul.

And then after two Gonzaga missed free throws, Smith elevated for what would be UNCG’s final chance. It was down, then it was out, rattling off the rim, off the glass, and into the arms of Norvell.

Gonzaga was a popular Final Four pick prior to Thursday, and its first-round opponent was as unheralded as 13-seeds come. The point spread closed at Gonzaga -12.5. Very few gave Greensboro a chance. It nearly got March Madness started with a stunning upset.

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Henry Bushnell covers soccer and college basketball for Yahoo Sports. Have a tip? Question? Comment? Email him at henrydbushnell@gmail.com or follow him on Twitter @HenryBushnell.

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