The NCAA tournament's first weekend saved the best for last when top overall seed Duke was pushed to the brink Sunday by a UCF team that seemed destined to pull off one of the biggest upsets of all-time.

The thrilling last two minutes of the game provided moments that define March Madness and in many ways made up for an otherwise mediocre first three days.

But there's no shortage of storylines coming out of the first weekend. Here's a look at the biggest winners and losers from four non-stop days of madness — encompassing 48 games altogether:

Winners

Duke. The whole "survive and advance" mantra of the NCAAs couldn't be truer for this heavily favored Blue Devils team that escaped a monumental upset to No. 9 seed Central Florida. It was Williamson's bulldozing basket against 7-foot-6 center Tacko Fall and R.J. Barrett's put-back — both plays made in the final 14 seconds — that saved Duke's national title pursuit in the 77-76 thriller. Ultimately, this is a win for fans, too, considering Duke's appeal as a must-watch spectacle unlike any team we've seen in years.

Virginia. The Cavaliers were trailing by six in the first half against a No. 16 seed on Friday. That sentence alone is enough to add more skepticism to the Virginia-choking bandwagon. But Virginia showed its mettle in eventually shaking off a Gardner-Webb team that tried to replicate UMBC's historic shocker last year, and then they outplayed ninth-seeded Oklahoma to reach the Sweet 16 where they'll face No. 12 seed Oregon with a trip to the Elite Eight on the line. The Cavaliers are national title contenders, sporting the best defense and three-point shooting in this entire tournament, and now the nerves have been calmed by two first weekend wins.

The ACC. With No. 1 seeds Duke, Virginia and North Carolina all advancing to the Sweet 16, No. 4 seeds Florida State (routing Murray State on Saturday) and Virginia Tech (dispatching Liberty on Sunday) gave the ACC five teams in the Sweet 16. While the league had the fifth best power conference rating in the NET, the NCAA's new metric replacing the RPI, the fact that the conference was top-heavy this year shouldn't take away from how good these five teams have been.

The Big Ten. The conference is sending its three best teams to the Sweet 16, but the league's merit came with its eight teams faring 7-1 in the first round. Double-digit seeds Iowa, Ohio State and Minnesota pulled off upsets — showing that its middling teams were better than their seeding line having played themselves off the bubble.

SEC's elite. LSU has been proving doubters wrong, coming together under interim coach Tony Benford to silence the skepticism that the SEC regular-season champs would falter with coach Will Wade still suspended amid his involvement in an FBI probe. Kentucky won two games without its leading scorer and rebounder, PJ Washington, helping the No. 2 seed's supporting cast grow in his absence (Washington is likely to be back for the Sweet 16). Tennessee has perhaps been the biggest survivor of this tournament, escaping a close call vs. No. 15 seed Colgate and then beating Iowa in overtime after blowing a 25-point lead. Even Charles Barkley's alma mater has had good fortune. The SEC tournament champion somehow avoided an upset vs. New Mexico State in a near-collapse in the game's final minute. And then the Tigers dismantled Kansas in a hot-shooting, tempo-controlling performance.

Cinderellas Liberty and UC Irvine. The Flames and Anteaters didn't advance to the Sweet 16, but their first round upset wins over Mississippi State and Kansas State gave us the bracket-busting upsets that make this tournament special. And like Cinderellas of yesteryear their bottom-to-top story lines felt bigger than the tournament itself, with Liberty's first-round hero Caleb Homesley scoring 30 points after being in the coach's doghouse and UC Irvine stepping out of the California shadows that UCLA and USC were supposed to rule.

The whole West Region. Thought to be the weakest region on the bracket, all four of the remaining teams have yet to stumble in this tournament and are all good enough to cut down the nets in Minneapolis in two weeks. Gonzaga, Texas Tech, Florida State and Michigan all looked dominant in dispatching their second-round opponents, beating them by a combined average of 19 points.

Oregon. The 12th-seeded Ducks weren't even supposed to be here. Had they not won the Pac-12 tournament's auto bid, they had no shot at an at-large bid. But that's the beauty of March, and coach Dana Altman's team peaked at the exact right time. Oregon's now won 10 games in a row and is playing defense at an elite level. The Ducks' upset of No. 5 Wisconsin didn't even feel like an upset and their second-round win over UC Irvine looked like exactly what it was: A power conference team emphatically ending a mid-major's Cinderella journey.

Carsen Edwards. The Purdue All-American guard was in a shooting slump, making just 21 percent of his three-pointers in the games leading up to the NCAA tournament. Consider the slump over following his 42-point performance the Boilermakers' blowout win over Villanova.

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Losers

UCF. March star Aubrey Dawkins (32 points off five three-pointers) and 7-foot-6 big man Tacko Fall (15 points, six rebounds) spearheaded a determined effort to bust brackets and notch a historic upset. The ninth-seeded Knights were leading Duke by four with two minutes to go and then one of the wildest final two minutes unfolded to give us an instant classic. Dawkins' play was, as Coach K described, "magnificent," and his father (UCF coach Johnny Dawkins) used a brilliant scheme to position his team for March glory — forcing Duke to shoot outside and making poor shooters like Tre Jones beat them.

Ja Morant and Murray State. All-American point guard Ja Morant gave us our first triple-double in seven years in an electrifying first-round performance to lift Murray State over Marquette. But, ultimately, Morant couldn't provide a Steph Curry-esque tournament run, as Florida State made quick work of the mid-major Racers.

Iowa, Maryland. Neither of these teams have any reason to hang their heads for losing their second-round games to better seeds. But it was how they lost that will sting well into the offseason. The 10th-seeded Hawkeyes stormed back from a 25-point deficit to force overtime against No. 2 seed Tennessee before exiting. And the Terrapins were ousted on an LSU game-winner that gave us our closest thing to a buzzer-beater in the first two rounds.

Kansas. The Jayhawks started off as the preseason No. 1 team in both the coaches and AP polls thanks to a roster mixed with great returning and incoming talent. But a deep postseason run never materialized as KU bowed out of these NCAAs with a second-round blowout loss to Auburn.

A promising 2018-19 started to unravel with a season-ending injury to Udoka Azubuike in December that forced coach Bill Self to rework the team's identity, which never fully materialized; top-10 recruit Quentin Grimes under-performed in an inexperienced backcourt and first-team All-American big man Dedric Lawson was forced to do too much all year. By the time second-leading scorer Legerald Vick unexpectedly left the team in February, the Jayhawks had already struggled enough to eventually lose out on a 15th consecutive Big 12 title — ending the program's epic streak of 14 seasons in a row.

Fletcher Magee and Wofford. The Terriers were a dark-horse to go as far as the Final Four, putting together a 30-win season and garnering a No. 7 seed as a mid-major from the Southern Conference. They played the part in a first-round win over Seton Hall and were poised to upset a Kentucky team playing without its top scorer and rebounder, PJ Washington. But the NCAA's all-time leading three-point shooter had his worst game at the worst possible time, going 0-for-12 from beyond the arc in a game in which Wofford needed just one or two of those treys to go down to turn the momentum and put the pressure on UK. Instead, it turned into a painful end to Magee's career and one of the tournament's biggest what-could-have-beens.

Almost Cinderellas. Speaking of what could've been, New Mexico State and Belmont win the first weekend award for Cinderellas that blew it. The 31-win Aggies stormed back from seven points down vs. Auburn in the game's final minute. Then guard AJ Harris passed up an opportunity to tie the game in favor of a pass out to Terrell Brown, who was fouled on a three-pointer. Down two, Brown only made one free throw but NMSU somehow kept possession after the second miss, setting up a last-second play that turned out to be an airball. Three chances to put on a glass slipper failed.

Belmont, meanwhile, was right there with Maryland in the game's closing minutes. But the Bruins' Grayson Murphy turned the ball over with four seconds remaining and the Terrapins escaped with a 79-77 win. Honorable mention in the Cinderella department are No. 15 seeds Bradley (led Michigan State with seven minutes to go) and Colgate (was within three of Tennessee with two minutes remaining) for their first-round near-upsets vs. No. 2 seeds.

Buffalo. The Bulls got drubbed by 20 points to a really strong Texas Tech team in a tough second-round draw, but the former Cinderella was certainly looking to get further than it did last year after stunning Arizona in the first round as a No. 13 seed. The committee rewarded its 32-win season by giving Buffalo a No. 6 seed and following an impressive demolition of Arizona State in the first round, the Bulls were even receiving sleeper Final Four talk.

Kansas State, Nevada. Two of last year's NCAA tournament overachievers seemed likely to repeat their success. Kansas State, an Elite Eight finisher in 2018, brought virtually everyone back from that squad but was bounced in the first round by Cinderella UC Irvine. And Nevada, a Sweet 16 finisher last year, had a top-5 team during the season but faltered late and despite having probably a better team than last year — still led by Caleb and Cody Martin — another second weekend run wasn't meant to be as No. 10-seeded Florida upset the Wolf Pack in the first round.

Mick Cronin, Cincinnati. The Bearcats probably got hosed by the selection committee by earning a No. 7 seed after winning the AAC tournament and posting 28 wins. But playing in nearby Columbus against a seemingly slumping Iowa team appeared to be a favorable draw for this gritty Cincinnati team that many forecasted to upset Tennessee in the second round. But once again, a Mick Cronin-coached Cincinnati team came up short. In nine NCAA tournament appearances, Cronin has only led the Bearcats to the Sweet 16 once. Last year, despite being a No. 2 seed, they bowed out in the round of 32. The coach's second-weekend fate doesn't stack up with his pedigree and the great teams he's had in recent memory.

Follow USA TODAY Sports' Scott Gleeson on Twitter @ScottMGleeson.