Calathes was 7-of-17 from the floor, including 4-of-6 from 3-point range, and had nine assists. He also was 6-of-7 from the free-throw line.
Calathes sparked a 15-0 run midway through the first half that gave the Gators (8-1) all the cushion they needed to beat the Dolphins (3-4) for the 17th time in the last 18 meetings.
Jacksonville led 14-12 early, then Calathes hit two 3-pointers, two free throws and had the pass of the night to Marresse Speights. Speights caught Calathes' underhand lob with one hand and, in the same motion, slammed it home.
Speights finished with 16 points on 7-of-16 shooting and added seven rebounds.
Dan Werner chipped in eight points, eight rebounds and three assists.
The Dolphins, coming off an 80-51 loss at No. 9 Michigan State and preparing for another tough road game at No. 5 Georgetown on Saturday, cut Florida's lead to 12 points, 74-62, with about 7 minutes to play but couldn't get any closer.
The difference in the game was Florida's 3-point shooting and ability to get to the free-throw line, especially early. The Gators were 7-of-13 from 3-point range in the first half, helping build a 47-33 lead at the break.
The Gators finished 9-of-23 from behind the arc and 19-of-23 from the stripe.
Jacksonville was 2-of-12 from behind the arc in the first half, but finished 6-of-16. The Dolphins were 19-of-35 from everywhere else on the floor -- hardly the kind of defense Florida coach Billy Donovan wanted -- and made 16 of 17 free throws.
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