How did top overall No. 1 seed Virginia lose in the greatest upset of all-time to UMBC?

Maryland-Baltimore County played inspired basketball for 40 minutes, and the No. 16 seeded Retrievers didn't take their foot off the gas pedal in upsetting No. 1 Virginia on Friday in the first round of the NCAA tournament in Charlotte. 

But the greatest upset of all time didn't happen on a buzzer-beater in a David-vs.-Goliath thriller. It was a 20-point blowout against the top overall seed in the tournament. As great as UMBC played behind 50% three-point shooting and Jairus Lyles' 28 points, Virginia also played a role in the outcome — by not playing up to the unbelievable standard the Cavaliers set throughout the entire 2017-18 season.

This is among the most stunning disappointments for a dominant team in college basketball history. How it happened is even more perplexing. Because Virginia was frankly very un-Virginia like all game.

The Cavaliers took bad, contested shots, didn't share the ball and were stale on offense. Defense, however, where Virginia has been dominant, was the most puzzling.

Virginia got beat in transition, which rarely happens. The Cavaliers let the opponent drive the lane and get to the basket at a higher rate than any game this season. Everything, including their hedging on ball screens, was slow. 

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How did the nation's best defense (allowing 53.4 points a game) let a team that ranks 212th in offensive efficiency score 74 points? Missing a key player, ACC Sixth Man of the Year De'Andre Hunter, is not an excuse.

Coach Tony Bennett, the national coach of the year, is all about tempo. The best teams in the country — Duke, North Carolina, the entire ACC — all fall victim to some degree to Virginia's tempo-controlling offense and nation-leading defense. Somehow, UMBC did what other teams couldn't do all season, including West Virginia and Virginia Tech (the two other teams to beat the Cavaliers in the regular season). The Retrievers dictated tempo from the start. 

UMBC coach Ryan Odom's game plan was perfect: Let his guards penetrate and fire at will, then play inspired defense in the process. 

"They got in foul trouble," Odom said after the game. "And that broke their momentum a little bit." 

Somewhere along the line, UMBC's confidence kept growing, and Virginia, uncharacteristically, panicked. Hurried. Took bad shots. Committed fouls.

Virginia lost a lot of battles it usually wins (getting out-rebounded, shooting 18% from three and tallying only five assists). UMBC came out swinging with knockout blows from the start, seizing control of the tempo. And the Retrievers handled Virginia's counter-punches incredibly well. 

The difference-maker undoubtedly was Lyles, who made a key bucket whenever Virginia would start to build momentum or chip away at the lead. 

Virginia was expected to be in the Final Four and a top pick to play in the national title game. Brackets have been busted everywhere.

UMBC will be considered among the greatest of Cinderellas.Nothing that Virginia did or didn't do takes away from that. But at the end of the day, Virginia's flop of epic proportions will be remembered just the same.