North Florida fell behind by double digits early and again late.
The Ospreys were unfazed, even though they were on the road and facing a ranked team.
Beau Beech scored 16 points, Travis Wallace added 15 and North Florida gave No. 10 Florida all it wanted in a 77-69 loss in the season opener Friday.
The Ospreys hit nine of their final 15 3-pointers and made it a seven-point game with 19.2 seconds remaining. But the Gators closed it out from the free-throw line. Florida finished 27 of 32 from the line.
Casey Prather scored a career-high 28 points for Florida, and Michael Frazier II added 19 points off the bench.
Although the Ospreys trailed 35-18 early — mostly because Florida made its first 17 free throws — they closed the first half with an 11-0 run to make it 37-31.
"When then went 17 of 17 from the line to start the game, and they're bad free-throw shooters, you're thinking you're going to be OK," UNF coach Matthew Driscoll said. "I'm really proud of our guys. The ability to sustain a couple punches, and like a boxing match, we kept getting up off the canvas."
Florida let North Florida, a team ranked No. 233 in the preseason Sagarin Ratings, hang around most of the afternoon. The Gators led by as many as 18 in the first half and 19 in the second half, but the Osprey kept coming back.
They had a chance to make it a nail-biter in the final minute, but Charles McCroy and Jalen Nesbitt missed 3s.
"North Florida had a lot of grit tonight," Florida coach Billy Donovan said. "They got down by 18 in the first half, they could have mailed it in or got pouty or moody. And you know what? They fought and they cut it to 16. They got down 19 (in the second half) and they fought back. When the roles were reversed and that happened to our team, we did not even show remotely close to the grit that North Florida showed.
"So maybe our guys can learn something from them."
The short-handed Gators won their 23rd consecutive opener — a much-needed tuneup before playing at 20th-ranked Wisconsin on Tuesday night.
But even before the schedule toughens, Donovan has a pretty clear indication about his team.
"We are light years away from even being a remotely good defensive team right now and light years away from even being a ranked team," Donovan said.
Prather hit 10 of 15 shots and made 8 of 11 free throws. His previous career high was 14. He had 23 last week in an exhibition game against Florida Southern.
"It's my last year, so I'm just trying to be as aggressive as I can," Prather said.
The Gators played two walk-ons because of suspensions and injuries.
Center Damontre Harris, forward Dorian Finney-Smith and point guard Scottie Wilbekin sat out the opener. Although they have been allowed to practice with the team, Donovan has given no timetable for their return. He confirmed after the game that they will be out again against the Badgers.
Making Florida even thinner, Frazier was uncertain to even play while recovering from mononucleosis and two more players were slowed by injuries. Frazier ended up playing 24 minutes. Donovan was more cautious with Will Yeguete (knee surgery) and Rutgers transfer Eli Carter (broken leg).
"Offensively, we're going to be OK. We'll get a little bit better in terms of shot selection," Donovan said. "My concern right now is on the defensive end of the floor. That's really a major concern I have right now. We gave up 38 points in the second half. No disrespect to North Florida, but we're going to play against higher-level people come Tuesday.
"We've got a long, long, long way to go — a long way to go. What's going on right now is not sinking in to these guys."