Hiwassee stayed in reach for most of the first half and tied the game at 45 in the second with Brandon Carpenter's 3-pointer. Western Carolina stormed away from there as Sinclair and Harrelson each hit 3-pointers to push the lead to 10.
The Catamounts (1-2) closed the game on a 27-8 run, limiting Hiwassee to just three field goals in the final 10 minutes.
Western Carolina limited the Tigers to 19-of-52 shooting (36.5 percent) and forced 21 turnovers. Kaseem Davidson was the lone player in double figures for Hiwassee with 10 and Jacob Elliot added seven with eight boards.