GAINESVILLE, Fla. (AP) — Colin Castleton is accustomed to being double-teamed every time he touches the ball, so he was pleasantly surprised — maybe even downright stunned — when Tennessee opted to guard him with a single defender in the second half.

“I’ve got to take advantage of that,” Castleton said.

He did. Castleton scored 20 points, including 16 in the second half, and Florida upended the second-ranked Volunteers 67-54 on Wednesday night.

Kyle Lofton added 14 points for the Gators, who delivered coach Todd Golden his most significant victory in his first season in Gainesville. It was Florida’s second Quad 1 win in the last two weeks.

The Volunteers, playing with their highest ranking in four years, lost for the first time in five games. They had won nine of 10.

“Our guys are disappointed,” Tennessee coach Rick Barnes said. “We’re better than this, but tonight we weren’t.”

Tennessee (18-4, 7-2 Southeastern Conference) looked like it had taken control midway through the second half. They outscored Florida by 10 points in the early going to take a six-point lead.

But the Gators (13-9, 6-3) stormed back behind Castleton, who scored 11 of 14 points as Florida rallied. The senior had a dunk, two free throws, a three-point play, a layup and a short jumper — essentially putting the team on his back down the stretch.

“They went small, and I felt like I had a mismatch,” Castleton said.

Myreon Jones and Will Richard chipped in nine points apiece for the Gators.

Zakai Ziegler led the Vols with 15 points on 6-of-19 shooting. Olivier Nkamhoua added 11 points and nine rebounds for the visitors, who also got 11 points and eight boards from Vescovi Santiago.

The Gators were red hot to start the game, making six of their first eight shots — including all three from 3-point range — while building a 17-4 advantage. But they quickly cooled against the nation’s best defense, missing nine of their next 11 as Tennessee made cut it to 22-21.

The Vols had it going coming out of the locker room, with Ziegler getting into the paint and making things happen. But it was short-lived — thanks mostly to Castleton.

“We gave them a chance to start believing in what they’re doing, and they took it,” Barnes said.

POLL IMPLICATIONS

Tennessee surely will drop a few spots in next week’s AP Top 25 college basketball poll.

BIG PICTURE

Tennessee: The Volunteers gave up 10 points in the opening four minutes of the games, a rare sluggish start for the nation’s best defense. Tennessee had held four of its first eight SEC opponents scoreless at the first media timeout, roughly the first four minutes of games. It was a sign of things to come.

“We kept fighting uphill all night long,” Barnes said.

Florida: The Gators are two games into the toughest stretch of their season. Coming off a loss at Kansas State, they have road games against Kentucky and Alabama up next. So to say they needed this one would be an understatement.

“It was a desperation game,” Castleton said. “We’ve got a tough schedule here and we’ve got to win games. We were able to claw and fight.”

IN THE HOUSE

Football coach Billy Napier watched the game from a few rows behind Florida’s bench alongside his two sons and receiver Ricky Pearsall. Former Florida tennis star Ben Shelton, the NCAA singles champion in 2022, also was in attendance. So was former Gators and NFL quarterback Doug Johnson.

UP NEXT

Tennessee hosts No. 25 Auburn and former coach Bruce Pearl on Saturday.

Florida plays at Kentucky on Saturday. The Gators have lost seven of eight in the series.

NO. 1 PURDUE 80, PENN STATE 60

WEST LAFAYETTE, Ind. (AP) — Mason Gillis broke the Mackey Arena record by making nine 3-pointers and finished with a career-high 29 points as Purdue beat Penn State.

Gillis went 10 of 14 from the field and 9 of 12 from beyond the arc. Zach Edey added his 18th double-double of the season with 18 points and 13 rebounds.

The Big Ten-leading Boilermakers (22-1, 11-1) have won nine straight overall, six straight in the series and are the only Power Five team with fewer than two losses this season.

Seth Lundy had 18 points to lead the Nittany Lions (14-8, 5-6).

NO. 14 MARQUETTE 73, VILLANOVA 64

MILWAUKEE, Wis. (AP) — Tyler Kolek scored 20 points and Marquette rallied down the stretch to beat Villanova and maintain a share of the Big East lead.

Kam Jones added 18 points for Marquette (18-5, 10-2), which has won four straight games and nine of 10.

Eric Dixon and Caleb Daniels scored 14 each for Villanova (10-12, 4-7), which committed a season-high 19 turnovers. Brendan Hausen added 12 points.

In a game neither team led by more than six until the final minute, Kolek put Marquette ahead for good at 63-62 by sinking two free throws with 4:32 remaining, starting a 10-0 spurt.

NO. 16 XAVIER 85, NO. 17 PROVIDENCE 83, OT

CINCINNATI (AP) — Jack Nunge had 23 points and 14 rebounds as Xavier held off Providence in overtime.

Colby Jones and Souley Boum each scored 20 for the Musketeers, who won a first-place showdown in the Big East without injured forward Zach Freemantle.

Noah Locke had 22 points and Ed Croswell added 21 for Providence (17-6, 9-3), which had beaten Xavier three straight times.

A layup by Boum put the Musketeers (18-5, 10-2) ahead 82-79 with 51 seconds remaining in overtime. A layup by Devin Carter cut Xavier’s lead to one with 24 seconds left. Boum hit one of two free throws, and Jared Bynum’s 3-point attempt from the left corner rimmed out at the buzzer.

NO. 25 AUBURN 94, GEORGIA 73

AUBURN, Ala. (AP) — Johni Broome scored 19 points and matched a career high with 18 rebounds, Allen Flanigan scored a season-high 22 points, and Auburn beat Georgia.

Wendell Green Jr. added 18 points and six assists and made two 3-pointers during a 17-0 first-half run for the Tigers (17-5, 7-2 Southeastern Conference).

Broome secured his seventh double-double of the season with 2:54 remaining in the first half, then added six points and six rebounds in the second half.

Mardrez McBride led the Bulldogs (14-8, 4-5) with 20 points.