The first Thursday and Friday of the NCAA tournament are two of the greatest days on the sports calendar. With March Madness canceled because of the coronavirus, here’s a full 16-game slate of memories featuring the maddest first-round matchups in tournament history involving teams from D.C., Maryland and Virginia. (Long live the Atlantic 11.)

1. 2018: No. 16 UMBC 74, No. 1 Virginia 54

Sorry, Virginia fans, but you knew it was coming.

UMBC, champions of the America East Conference, became the first No. 16 seed to defeat a No. 1 seed in the NCAA men’s basketball tournament, and the Retrievers did it in blowout fashion at Charlotte’s Spectrum Center.

Jairus Lyles led UMBC, which made 12 of its 24 three-point attempts, with 28 points. The Retrievers scored 53 points in the second half against a Virginia defense that was allowing 53.4 points per game.

Fans celebrated by tweeting photos of their retrievers at UMBC’s Twitter account, which had a legendary performance of its own and coaxed an apology out of CBS studio analyst Seth Davis, who foolishly advanced Virginia to the next round in his bracket shortly after tip-off.

“We talk about it all the time: the adulation, the praise, it comes, and we got a lot of that this year,” Virginia Coach Tony Bennett said after the loss. “Then on the other side, there’ll be blame. That can’t in the end define these guys and our team or us because it was a remarkable season, but we got thoroughly outplayed. That’s the reality of it.”

Bennett’s Cavaliers wouldn’t be defined by their historic loss. They bounced back to win their first NCAA men’s basketball title last year, and they will be the reigning champions for at least another 12 months.

2. 1989: No. 1 Georgetown 50, No. 16 Princeton 49

UMBC’s upset wouldn’t have been quite as notable if 16th-seeded Princeton had finished the job against top-seeded Georgetown 19 years earlier. Trailing by one, the Tigers had two shots for the lead in the final seconds, only to be denied by Hoyas freshman center and shot-blocking sensation Alonzo Mourning.

Mourning’s game-saving block of Princeton center Kit Mueller’s shot after an inbounds pass with one second remaining was controversial. Mueller thought Mourning made contact with his hand.

“It was a tough call,” said Mourning, who finished with 21 points, 13 rebounds and seven blocks. “It could have gone both ways. … I know I didn’t touch the guy, but the call could have gone the other way. Thank God it didn’t.”

“It would be an understatement to say Princeton deserved to win this game,” Georgetown coach John Thompson told reporters. “Those kids showed a lot of courage and fortitude.”

3. 1991: No. 15 Richmond 73, No. 2 Syracuse 69

Two years after Georgetown survived against Princeton, Richmond knocked off the Hoyas’ biggest rival and became the lowest-seeded team to win a game since the tournament expanded to 64 teams in 1985.

“I told them that great things can happen in basketball, but we almost have to play a flawless game,” said Spiders coach Dick Tarrant, whose team never trailed against Syracuse and fed off the energy of the pro-Richmond crowd at Maryland’s Cole Field House.

Tarrant was no stranger to being on the winning side of NCAA tournament upsets. In 1984, the 12th-seeded Spiders upset an Auburn team led by Charles Barkley in the first round. In 1988, 13th-seeded Richmond knocked off defending national champion Indiana.

4. 1997: No. 15 Coppin State 78, No. 2 South Carolina 65

The Eagles didn’t care that they were 30-point underdogs against the Gamecocks.

“We didn’t even know it was South Carolina out there,” Coppin State forward Reggie Welch, who had a game-high 15 rebounds, said. “We kept on getting confidence, and before you knew it, we were up. We took it five minutes at a time — there’s five minutes, there’s five more."

“As the game went on, we started feeling more confident,” said Danny Singletary, who scored 18 of his game-high 22 points in the second half. “I started saying to myself, ‘Nobody can stop me except myself.’ They started losing confidence. … And when we knew we had them on the ropes, we were not going to let them up.”

The Washington Post reported that a Coppin State player used a disposable camera to record the celebration in the victorious locker room. Led by coach Fang Mitchell, the Eagles almost secured a berth in the Sweet 16 but lost to Texas, 82-81, in the second round.

5. 2001: No. 15 Hampton 58, No. 2 Iowa State 57

The lasting image of Hampton’s win over Iowa State was of coach Steve Merfeld flailing his arms and legs as freshman forward David Johnson lifted him in the air while players and the Hampton band celebrated on the court in Boise.

Center Tarvis Williams finished with 16 points, 13 rebounds and six blocks to lead the Pirates, who were making their first NCAA tournament appearance. The Cyclones had a chance to win, but point guard Jamaal Tinsley missed a layup with one second remaining.

“They’ll be talking about this for a long time,” Iowa State coach Larry Eustachy said.

6. 2013: No. 15 Florida Gulf Coast 78, No. 2 Georgetown 68

Florida Gulf Coast, better known as “Dunk City,” sent the Hoyas home early with a surprising 10-point win at Philadelphia’s Wells Fargo Center. The defeat came three years after Georgetown, which had failed to advance to the second weekend of the tournament since its Final Four run in 2007, suffered an embarrassing first-round loss to 14th-seeded Ohio.

“I wish I could,” Georgetown coach John Thompson III said when asked if he could identify a common thread in his team’s streak of postseason disappointments. “Trust me, more than anyone on this earth I’ve tried to analyze it, think about it, look at it, think about what we should do differently. And I don’t know.”

Sherwood Brown led FGCU with 24 points, while Otto Porter Jr. had 13 points and 11 rebounds in defeat for the Hoyas. The loss was commemorated in one of the greatest headlines in the history of The Post two years later: “Georgetown invites 2 Chainz to Hoya Hoops Madness, where he’ll probably get upset by 15 Chainz.” (Credit to Matt Bonesteel and Dan Steinberg for that zing. It’s okay to laugh, Hoyas fans.)

7. 2012: No. 15 Norfolk State 86, No. 2 Missouri 84

Norfolk State became the fifth 15-seed and the third from the commonwealth of Virginia to pull off a first-round upset in the NCAA tournament, and it busted President Barack Obama’s bracket in the process.

Kyle O’Quinn had a game-high 26 points and 14 rebounds for the Spartans, who lost an exhibition game to Division II Elizabeth City by 12 points in the preseason.

“Which one of you guys is going to call Obama and tell him we messed up his bracket?” Norfolk State assistant coach Wilson Washington shouted in the victorious locker room.

8. 2006: No. 11 George Mason 75, No. 6 Michigan State 65

In the days leading up to the game, George Mason listened to pundits, including CBS broadcaster Billy Packer, say it didn’t deserve an at-large bid after losing in the semifinals of the CAA tournament. The Patriots would more than prove their worth over the next three weeks.

The win that sparked the most improbable Final Four run in tournament history came against powerhouse Michigan State, which had lost in the national semifinals the previous season. The Patriots knocked off the Spartans despite the absence of their second-leading scorer, senior guard Tony Skinn, who had been suspended one game by coach Jim Larranaga for punching a Hofstra player in the groin in the team’s CAA tournament loss.

Folarin Campbell led the Patriots with 21 points, while Will Thomas added 18 points and 14 rebounds.

“It’s about time!” fifth-year senior Lamar Butler said after the win. “Coach had never won a tournament game, George Mason had never won — there are so many thoughts going through my head. The CAA is starting to get the recognition they deserve. We’re starting to get the recognition we deserve. We proved a lot of naysayers wrong.”

9. 2003: No. 6 Maryland 75, No. 11 UNC Wilmington 73

Maryland, the defending national champions, trailed 73-72 after a pair of free throws by UNC Wilmington’s Aaron Coombs with five seconds left. After the Seahawks called a timeout to set their defense, Maryland forward Tahj Holden inbounded the ball to Drew Nicholas, who dribbled his way up court and let a shot fly from in front of the Terps’ bench just before the buzzer sounded.

It found nothing but net.

“There’s nothing better,” Nicholas said. “In front of 20,000 fans, NCAA tournament? It can’t get better. I just kind of ran up and got the ball and I just took it far as I could and tried to make something happen. I know the shot didn’t look the prettiest, but it went in. I couldn’t believe it when it went in. Around this time, it’s all about winning and advancing.”

Nicholas’s shot spoiled a brilliant performance by UNC Wilmington freshman guard John Goldsberry, who made his first eight shots, all of them from long range, and finished with a game-high 26 points.

10. 2006: No. 9 George Washington 88, No. 8 UNC Wilmington 85 (OT)

George Washington’s first NCAA tournament win since 1994 didn’t come easily. The Colonials improved to 27-2 by overcoming an 18-point deficit with 11 minutes remaining in regulation to force overtime and a four-point deficit in the final two minutes of the extra period.

“I can’t tell you about anything in the past; the only thing I can tell you is this team is very focused and very hungry and they’re just trying to fulfill their dreams,” GW Coach Karl Hobbs said. “It came down to a will, a will to win.”

“We get to have another chance, that’s what it means,” said Pops Mensah-Bonsu, who scored 10 points in his first game back from a knee injury that sidelined him for two weeks. “We finally got a win in the tournament. We got over that hump. Now it’s time to keep it moving.”

The Colonials lost to top-seeded Duke, 74-61, in the next round.

11. 2007: No. 11 VCU 79, No. 6 Duke 77

VCU point guard Eric Maynor hit a 14-foot jumper with 1.8 seconds remaining to give the Rams their first NCAA tournament win since 1985 and Duke its first first-round loss since 1996. The Blue Devils led by nine points with 12 minutes left.

“It felt like it was good,” Maynor, who finished with 22 points, said. “And for it to go in, I said to myself, ‘Man, I just hit the game-winner on Duke University.’”

Duke’s Greg Paulus, who scored a career-high 25 points, missed a half-court shot off the backboard as time expired, prompting chants of “C-A-A! C-A-A!” at Buffalo’s HSBC Arena.

“We’re not George Mason,” Maynor said. “We’re this year’s VCU, though.”

Pittsburgh sent the Rams home in the second round, but VCU would make its own improbable Final Four run four years later.

12. 1995: No. 14 Old Dominion 89, No. 3 Villanova 81 (3 OT)

Petey Sessoms scored seven of his 35 points in the third overtime to lift the CAA champions to their first NCAA tournament win since 1986.

“This is not a knock against Villanova, but you were expecting them to win this game, but we really expected to win,” ODU guard Mike Jones said. “Each overtime was another opportunity. When it ended, we made a conscious effort to keep things low-key. We have another game Sunday, and no one is going to expect us to win that game either.”

It was the seventh game in NCAA tournament history to go at least three overtimes. At least one person in Albany’s Knickerbocker Arena had no idea the game lasted so long.

“To be honest, until I looked at the stat sheet, I didn’t know it was three overtimes,” said Villanova Coach Steve Lappas, whose team missed shots to win at the end of regulation and the second overtime.

Old Dominion went on to lose to Tulsa, 64-52, in the second round.

13. 2001: No. 3 Maryland 83, No. 14 George Mason 80

Maryland’s first run to the Final Four under coach Gary Williams was nearly ended in the first round by 30-year-old Gulf War veteran George Evans, who scored a game-high 27 points in George Mason’s upset bid.

The Patriots, who led for most of the game, trailed by one with 28 seconds to play after Maryland’s Terrence Morris missed a pair of free throws. On George Mason’s ensuing possession, Tremaine Price’s bounce pass inside to Evans went through the three-time CAA player of the year’s legs and out of bounds with six seconds remaining. Juan Dixon was fouled and made two free throws to give Maryland an 83-80 lead, and Price missed a potential game-tying shot at the buzzer.

“We were scared,” Dixon, who scored 22 points, said.

“It will take them days to recover from this,” George Mason coach Jim Larranaga said of his team. “You give so much. You’re not going to replenish it with one night’s sleep. … Words really can’t express how difficult it is to deal with such a close loss and an opportunity to move on.”

14. 1989: No. 5 Virginia 100, No. 12 Providence 97

This game ended in regulation, wasn’t an upset and didn’t feature a buzzer-beater, but with 17 ties, 20 lead changes and nearly 200 combined points, it sure must have been exciting to watch.

Virginia’s Richard Morgan hit a pair of free throws with 17 seconds left, and Providence guard Matt Palazzi missed a pair of three-point attempts at the other end to clinch the Cavaliers’ spot in the second round.

“Palazzi got a great shot on the first one,” Virginia guard John Crotty told reporters. “After he got the ball back it was like, ‘Oh God, he won’t miss another one.' Fortunately he did, though.”

“If we had to play the game 100 times over, we’d do the same thing at the end,’ first-year Providence coach Rick Barnes, who spent the previous season at George Mason, said. “Matt has been our best three-point shooter. He had two good shots at it, but they just didn’t go in.”

Morgan scored a game-high 33 points, and Crotty added a career-high 24 points and 10 assists.

15. 1980: No. 7 Virginia Tech 89, No. 10 Western Kentucky 85 (OT)

Led by Maryland transfer Billy Bryant, Western Kentucky, which was coached by Gene Keady before his legendary career at Purdue, took an 18-point lead into halftime against the Hokies. The deficit seemed insurmountable, especially given that the game was being played on the Hilltoppers’ home court in Bowling Green. Dale Solomon had other ideas.

Virginia Tech scored the first eight points of the second half. After being held scoreless in the first half, Solomon, the Hokies’ center, scored 20 points in the second to help force overtime. Solomon scored the go-ahead basket in the extra period.

The Hokies lost to second-seeded Indiana in the second round.

16. 1985: No. 5 Maryland 69, No. 12 Miami (Ohio) 68 (OT)

Maryland coach Lefty Driesell figured the game was over after Miami’s Ron Harper stepped to the line for a free throw with 37 seconds remaining in overtime and the Redskins leading 66-63. After all, the Terps, who blew an 11-point lead in regulation, had just lost their best player.

“When Harper dunked and Len Bias fouled out, I thought, ‘Well, the good Lord doesn’t want us to win today. Let’s just get outta here,’" Driesell said. “But the players never gave up.”

Harper, who scored a game-high 26 points and went on to win five NBA titles, missed his free throw. With Miami clinging to a 68-67 lead with 17 seconds left, Adrian Branch stole Harper’s inbounds pass intended for Todd Staker and put up a shot. It was off the mark, but Jeff Adkins tipped it in for the game-winning basket.

“I ain’t used to kissing men,” Driesell told The Post afterward, “but when we won, I went over and kissed Adrian for making that last steal. It was an unbelievable way to come back and win."

BONUS: 1985: No. 13 Navy 78, No. 4 LSU 55

Maryland advanced to play 13th-seeded Navy, which dominated LSU in the first round behind 18 points and 18 rebounds from legendary center David Robinson and 20 points from Vernon Butler. LSU coach Dale Brown said his Tigers were “completely embarrassed."

“People who see this score will probably say that LSU stunk and Navy was lucky,” Navy coach Paul Evans said. “But it doesn’t matter to us. We know what we’ve done.”

Navy’s season ended in the second round with a 64-59 loss to Maryland. The teams wouldn’t meet again until 2018.

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