Florida trailed 46-42 with 7:50 to play when Frazier drained his third shot from behind the arc. Seniors Scottie Wilbekin, Casey Prather and Pat Young did the rest.
Wilbekin hit a nifty baseline floater, Prather followed with his first of two spinning layups and then Florida (11-2) went ahead for good on Young’s three-point play. Dorian Finney-Smith’s 3-pointer gave the Gators some cushion down the stretch, and they closed it out from the free throw line — barely.
"There were some moments that were pretty good," said Florida coach Billy Donovan, who took blame for his team’s lackluster effort early.
Florida missed six of eight free throws in the final minute.
But the Spiders (10-5) were unable to make those mistakes hurt.
Cedrick Lindsay led Richmond with 19 points, and Kendall Anthony added 15.
Young finished with 15 points for Florida. Prather had 12 and Wilbekin added 10.
Florida didn’t play particularly well, shooting 26 percent from 3-point range, turning the ball over 14 times and managing just 10 assists.
"We would be great on a horse track because we play like this sometimes," Donovan said, holding his hands next to his eyes. "We’ve got these blinders on and they can’t see left or right. They can only see directly in from of them. … They drive the ball and there’s guys standing wide open and they don’t see them."
Wilbekin, Florida’s starting point guard, missed nine of his first 10 shots and had one assist and no turnovers in the first half. Donovan challenged him at the break, but he still seemed hesitant to shoot and had trouble finding open teammates.
He did manage to get the ball to Prather for some key shots.
"To start the game off, we were flat and we didn’t have a lot of energy," Frazier said. "But as the game went on, I think we did a good job of picking it up."
The Gators need one more home win — they open Southeastern Conference play against South Carolina on Wednesday night — to match the school record of 24 straight set between 2006 and 2007.
The latest victory was in doubt midway through the second half.
Richmond made six 3s in the second half, including five by Lindsay. Lindsay answered consecutive 3s by Frazier with 12-plus minutes remaining with a shot from the wing. He drained another one that put the Spiders up 41-38. Richmond was up 46-42 with 8:34 remaining, but Frazier’s third 3 sparked the comeback.
Prather’s second spinning layup resulted in a three-point play and put Florida ahead 55-50.
The Gators carried that momentum to the other end, ratcheting up their defensive effort. Richmond fouled repeatedly in the closing minutes, but couldn’t take advantage of Florida’s misses.
"We came into the game with a lot of heart," Richmond coach Chris Mooney said. "We were tough. There were some things we could have done better, but as far as our effort, confidence and toughness, that cannot be questioned."
Florida shot 44 percent from the field despite going 5 of 19 from behind the arc and really handled Richmond inside. The Gators outrebounded the Spiders 44-22 and outscored them 38-20 in the paint.
Donovan’s team has won five straight and 10 of 11 — the only loss a buzzer-beater at then-No. 12 Connecticut. So this was another quality win for Florida’s non-conference schedule.
Richmond, meanwhile, lost for the first time in regulation since Nov. 23. The team’s last two losses — to Wake Forest and Ohio — came in overtime.
"If we were a bunch of seniors, I’d say this might be where we are as a team, but we have four sophomores who are working really hard to get better, so we have improvement in our future," Mooney said.