To call Fairleigh Dickinson's 63-58 NCAA Tournament victory over Purdue improbable would be an understatement, and the odds back that up.
The Knights, who were only in the tournament by virtue of Merrimack being ineligible despite winning the Northeast Conference Tournament, were 301st by NET heading in and 23.5-point underdogs to Purdue.
By halftime, it was clear something special was brewing as FDU hung around. However, it wasn't until Sean Moore hit a 3-pointer with just over a minute left to make it a five-point game that it became apparent that not only could FDU win, but FDU would win.
MORE: Who is Sean Moore? FDU guard comes up clutch vs. Purdue
It's just the latest instance of the madness of March. But is it the maddest March has ever been? Going by point spread alone, FDU did, in fact, pull off the greatest upset in NCAA Tournament history, topping No. 15 Norfolk State defeating No. 2 Missouri in 2012 as 21-point underdogs.
MORE: Fairleigh Dickinson's upset of Purdue, by the numbers
Here's a look at some of the biggest upsets in NCAA history.
Biggest upsets in NCAA Tournament history, by point spread
In terms of point spread, Fairleigh Dickinson made history with its 63-58 victory over Purdue in the first round of the 2023 NCAA Tournament. The Knights were 23.5-point underdogs against the No. 1-seeded Boilermakers, and they qualified only because NEC Tournament champion Merrimack was ineligible.
BENDER: Purdue deals with shock of suffering historic upset
It tops the 21-point spread overcome by Norfolk State when the Spartans defeated Missouri in 2012, and it also beats out UMBC's 20.5-point underdog shocker over Virginia in 2018, the only other men's No. 16 victory over a No. 1 seed.
A look at the top five upsets in NCAA Tournament history, based on point spread.
| Year | Matchup | Spread | Result |
| 2023 | No. 1 Purdue vs. No. 16 Fairleigh Dickinson | Purdue -23.5 | FDU 63, Purdue 58 |
| 2012 | No. 2 Missouri vs. No. 15 Norfolk State | Missouri -21 | Norfolk State 86, Missouri 84 |
| 2018 | No. 1 Virginia vs. No. 16 UMBC | Virginia -20.5 | UMBC 74, Virginia 54 |
| 1993 | No. 2 Arizona vs. No. 15 Santa Clara | Arizona -19.5 | Santa Clara 64, Arizona 61 |
| 2022 | No. 2 Kentucky vs. No. 15 Saint Peter's | Kentucky -18 | Saint Peter's 85, Kentucky 79 |
One thing that jumps out is how recent most of these games are. Three of the top five are in the past five years, and all but one is in the past 11. That Arizona upset from 1993 is not to be confused with Arizona's first-round loss to Princeton on Thursday; the Wildcats lost as 15.5-point favorites, good for the 10th-biggest upset ever by spread.
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In the case of Purdue, it's the kind of loss that can haunt a program. Fairleigh Dickinson, meanwhile, can hang its hat on it forever. For more scope, Fairleigh Dickinson's moneyline for this game was +2000 (or 20-1), meaning a $100 bet would net $2,000.
March Madness has the entire Norfolk State vs. Missouri game posted on its Youtube page. It was the Spartans' first win over a ranked Division I team.
MORE: How FDU stacks up against UMBC in 16 vs. 1 March Madness upsets
It seems unlikely this record will be broken for a long time, although there were those who thought UMBC would be alone in the men's 16-over-1 club a lot longer than the Retrievers turned out to be.
