DAYTON, Ohio (AP) -- When Lamar trailed by double digits in the second half of its NCAA first-round game on Wednesday night, there was a lingering feeling that the Cardinals had Vermont right where they wanted them.
Leads were poison on the first night of the First Four at the University of Dayton.
But on the second night, early advantages lasted and the incredible comebacks were muted.
Cool-headed, hot-handed freshman Four McGlynn, who topped the Catamounts with 18 points, led the way in a 13-0 first-half run that gave Vermont a lead that it never let slip away in a 71-59 victory over Lamar.
In the nightcap, South Florida's nasty defense flirted with perfection in paving the way to a stunning 36-13 halftime lead -- yes, you read that right, 36-13 -- before cruising to a 65-54 win.
The first two games of the tournament, however, were nightmares for teams in front.
With President Barack Obama and British Prime Minister David Cameron watching from the front row, Mississippi Valley State blew a 16-point lead with 5:07 left in falling to Western Kentucky, 59-58.
It was the biggest comeback ever in the final 5 minutes of an NCAA tournament game.
Then Obama and the Cameron left, barely missing out on the biggest comeback in NCAA tournament history.
Iona scored 55 points in the first 16 minutes and built a 25-point lead only to lose to BYU, 78-72, in Tuesday's nightcap.
But apparently those incredible turnarounds had only a 24-hour shelf life.
The win by Vermont (24-11) sends it into a second-round matchup with top-seeded North Carolina on Friday in Greensboro, N.C.
The biggest win in school history came in 2005 when the 13th-seeded Catamounts stunned fourth-seeded Syracuse 60-57 in overtime. This year's team welcomes another shot at history.
"The Syracuse game was a huge win for Vermont and the community," said forward Brian Voelkel, who had only three points but 12 rebounds. "Obviously, we're going to come into North Carolina with a lot of confidence and hopefully we can pull off another upset and give the people of Burlington something to cheer about."
The Catamounts, champions of the America East tournament, played gritty defense and also shot 50 percent from the field, blending an inside presence with McGlynn's touch from the perimeter.
Devon Lamb and Mike James each had 16 points and Anthony Miles 14 for Lamar (23-12), which had won six in a row since first-year coach Pat Knight ripped his seniors after a loss in late February. He said then that they were "stealing money being on scholarship" and that his players had problems "off the court, on the court, classroom, drugs."
But after the NCAA loss, an emotional Knight fought back tears as he spoke about players who he said would turn the Lamar program around.
"These guys did a heck of a job of leaving their legacy. If there are people that disagree about that, they're morons," Knight said, sounding a little like his father, Hall of Fame coach Bob Knight. "These guys just made Lamar relevant again. What a ride. These guys, boy, I'll be talking about them until the day I die."
Victor Rudd Jr. had 15 points, Anthony Collins 12, Augustus Gilchrist 11 and Jawanza Poland 10 in the rout by South Florida (21-13), which moves on to play fifth-seeded Temple in Nashville on Friday.
But it wasn't the Bulls' shooting -- 57 percent from the field -- that left the biggest mark on Cal (24-10). The Bulls' defense contested every shot, scrapped for every loose ball and muscled away rebounds.
Collins had seen Mississippi Valley State and Iona blow those big leads. He wasn't going to let it happen to the Bulls.
"Those teams played up and down, playing fast, but they still would come down and take bad shots," he said. "We wanted to run some time and get good shots."
They sure did.
No wonder Cal coach Mike Montgomery was so stunned by the horror show of a first half.
"I didn't imagine that happening," he said.
It was the first NCAA tournament win ever for South Florida's program.
"We're all thrilled -- the president, the AD -- it's always great to keep your bosses happy," coach Stan Heath said. "But we didn't want to come here for just one game. We did want to prove that we belong and that we're legit. The kids took that to heart."
And they did it by storming to a lead and then -- unlike others -- not giving it up.
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