The Buccaneers (18-9, 13-3 Atlantic Sun Conference) closed the first half on a 23-5 run to lead 51-27 at the break, shooting 54.5 percent from the field (18 of 33).
The Dolphins (16-8, 10-5) rallied to cut the deficit to 10 points, at 70-60 with 3:09 left. East Tennessee State hit 10 of 10 from the free-throw line to seal the win.
Keith McDougald scored 13 points to pace Jacksonville, which saw its two-game winning streak end. The Dolphins fell 2.5 games behind second-place East Tennessee State in the conference standings.