The junior guard quickly redeemed himself by delivering a timely block of VJ King's shot with 6 seconds remaining, Braian Angola grabbed the rebound and fed to M.J. Walker for a dunk with 1 second left that clinched the Seminoles' 80-76 win on Saturday.
In just 11 seconds, Mann went from feeling stress to elation after a hard-fought win that helped FSU (17-6, 6-5 Atlantic Coast Conference) avenge last month's loss to Louisville that broke a 28-game home winning streak.
"I missed the free throws and I knew I had to guard the ball and get a stop," said Mann, FSU's top scorer who entered the game making 72 percent from the foul line. "I knew they'd be driving to the basket aggressively, I just had to buck up and play defense.
"It was just happening in the moment. I used my defensive principles and got the stop."
Phil Cofer scored 11 of his 16 points in the second half, Angola added 13 and Mann and Christ Koumadje each added 11 for FSU, which broke a 57-all tie in the second half with six unanswered points and ending with Cofer's 3-point play with 7:36 left.
The Seminoles' lead stretched to eight a couple of times before they had to fight off the Cardinals' late charge that got them within 78-76 with 24.7 seconds remaining. Mann's missed free throws with 17.4 seconds left opened the door for Louisville before his block finally tilted things toward FSU in a tight game featuring 11 lead changes and seven ties.
"We're very fortunate to hang on there for a victory," said Seminoles coach Leonard Hamilton, whose team shot 52 percent in the second half and 45 percent overall.
"I was very proud of our guys because Louisville took us to the woodshed at our place. I felt like our guys were a little bit more poised with the exception of the two turnovers there toward the end of the game."
In bouncing back from its loss to Wake Forest, FSU also handed Louisville (16-7, 6-4) its second straight ACC defeat for the first time in nearly two years and third in four games. The Cardinals made just 12 of 33 from the field after halftime (36 percent) and were outrebounded 43-34.
"They came in here and exposed us on defense and outrebounded us, which we knew was going to be a big key to the game," Cardinals interim coach David Padgett said. "So, give them credit. That team was desperate for a win and they came out and showed it."
Deng Adel had 19 points and Quentin Snider 15 for the Cardinals.
Florida State: With three starters in foul trouble, Cofer stepped up with critical points that maintained the Seminoles' lead once they got it for good. CJ Walker and Trent Forrest each added 10 points, with Forrest grabbing a team-high nine rebounds off the bench. Neither was easy against Louisville, which entered the game 13-1. "We just kept our composure and came out with the win," Cofer said. "We made great plays from the end of the half, just tried to play hard and not look at the scoreboard."
Louisville: The Cardinals had their chances but shot 36 percent in the second half and missed several free throws down the stretch that could have closed the gap much sooner. Snider's five straight points got them within a basket with another opportunity to tie, but King's blocked attempt led to the clinching basket.
Ray Spalding (13 points, 9 rebounds) went down midway through the second half with left leg cramps before leaving the game late with a sprained right ankle. He will be evaluated on a daily basis.
Florida State hosts No. 2 and first-place Virginia on Wednesday, seeking its fourth win this season over a ranked foe.
Louisville hosts Syracuse on Monday night, seeking its fourth straight series victory over the Orange.
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