Hill had two follow shots in the final 14.6 seconds in a wild finish for the Runnin' Bulldogs (10-8, 2-2 Big South). The 6-foot-5 freshman scored a career-high 15 points on 6-of-6 shooting and had six rebounds in 28 minutes.
Hill's follow shot of a Donta Harper miss with 14.7 seconds left gave Gardner-Webb a 65-64 lead, but Coastal Carolina (7-8, 2-2 Big South) was determined to complete a furious second-half rally. Guard Warren Gillis drove the length of the court and converted a layup with 8.4 seconds left to give the Chanticleers the lead - setting up Hill's heroics.
Max Landis launched a corner three-pointer that missed the goal, but Hill was free underneath, and calmly knocked down the game winner.
"We certainly made this one interesting," said Gardner-Webb head coach Chris Holtmann. "Give Coach Ellis and Coastal credit for the way they competed after getting down late in the game. I'm very happy for our players.
"We played well in stretches, but we need to play smarter and with more assertiveness down the stretch."
Gardner-Webb led 62-51 with 3:38 remaining in the game, but Coastal went on a 12-0 run to take its first lead of the game on a Gillis 15-footer with 53.4 seconds left.
Tashan Newsome scored 12 of his 17 points in the first half, and Gardner-Webb led by 12 points on a Kevin Hartley three-pointer with 5:14 to play before halftime. Coastal Carolina showed life in the final five minutes, however, using a 12-4 run to trim the margin to 30-26 at the break on a steal and layup with 24 seconds left by Justin Daniel.
Jumpers by Harper and Newsome, two free throws by Hill and Hartley's second three-pointer of the game powered an 11-4 run by Gardner-Webb to start the second half, and the lead would get back to 12 points on a Hill free throw with 14:56 to play (44-32).
The Chanticleers whittled the lead down to 48-44 with another strong spurt, but Hill made short jumpers and Harper scored five points to spark a 14-7 rally that put the 'Dogs on 62-51 with 3:28 to play.
Raffa converted a three-point play with a layup and free throw on Coastal's next possession, nailed a short jumper with 2:19 left to cut the lead to 62-58 and drilled a three under duress with 1:38 remaining to cut the lead to 62-61.
A Gardner-Webb turnover with 1:13 to play on an inbounds play gave the Chanticleers the ball back, and Gillis drained his first big shot with 53.8 seconds to play for a 63-62 lead.
A pair of timeouts allowed Gardner-Webb to set up a play, but Harper was forced to beat the shot clock with his jumper. Hill beat two Chanticleers to the rebound just under the rim, and tipped the miss home for a 64-63 lead with 14.7 seconds on the clock.
After Gillis coast-to-coast layup, Newsome took the inbounds pass 75-feet from the basket, dribbled inside the arc along the left side and found Landis open in the corner. The sophomore guard's shot overshot the rim, allow Hill his game winner.
Harper led Gardner-Webb with 18 points and Tashan Newsome had 17 to supplement Hill's big night. The Runnin' Bulldogs shot 50.0 percent in the second half, and 48.9 percent for the game to improve to 7-1 in Paul Porter Arena this season. GWU is 16-5 at home over the past two campaigns.
Hartley connected on both of his three-point attempts Wednesday before fouling out, and has now made a sizzling 17 of his last 24 attempts from long range (70.8 percent). Tyler Strange added eight points and five assists in 34 minutes at point guard.
Anthony Raffa had 25 points for the Chanticleers, who shot 57.1 percent in the second half. The Chants shot 49.1 percent for the game, and out-rebounded Gardner-Webb 21-11 in the second half to help with the comeback.
Charles Ashford, Gillis and Eganga each had eight points for Coastal Carolina.
Gardner-Webb will host Radford at 7:00 pm on Saturday in another tough Big South Conference test. The Highlanders beat Longwood, 82-72, Wednesday night at home to move to 2-2 in the league.