The Vols, coming off their dramatic last second win at Georgia Tech Sunday, trailed briefly early in the second half, 29-28, before taking control. UT proceeded to outscore the Bucs 22-5 in the next 8 minutes to improve to 4-1 on the season.
Watson and Slay, who had a season-low 10 points, were the only Vols in double-figures, while Derek Stribling added a career-high 8 points off the bench. Kevin Warzynski led Charleston Southern with 14 points.
The Vols, who led by as many as 10 points in the first half, took a 28-23 advantage into halftime. Charleston Southern scored the first six points of the second half to take a 29-28 advantage at the 17:15 mark.
The Vols travel to West Virginia Saturday to take on the Mountaineers in a 4 p.m. tipoff. West Virginia beat the Vols on a three-pointer in the final seconds last season at Thompson-Boling.