Greenwood, who scored 16 points for the Chanticleers (11-4, 4-1 Big South Conference), hit his go-ahead shot with 24 seconds left.
Raffa, who cut a 77-74 Charleston Southern lead to one point with 1:47 left, added a free throw with 9 seconds remaining for the final margin.
Coastal Carolina led 69-63 with 1:01 left in regulation, but the Buccaneers (10-6, 4-2) rallied with two free throws and a layup by Mathiang Muo and a 3-pointer by Arlon Harper with 4 seconds left. Harper finished with 22 points and Muo 20 for Charleston Southern.
The Buccaneers led 26-17 in the first half but Coastal Carolina cut the margin to 26-25 at halftime.
There were 13 ties and 16 lead changes in the game.
- Sports & Recreation/Basketball
- Sports & Recreation
- Charleston Southern
- Coastal Carolina