Travon Woodall contributed 12 points and 10 assists for the Panthers (5-1), who jumped out to a 42-25 halftime lead and were never headed.
Cameron Wright donated 13 points and Talib Zanna added 10 points and 15 rebounds for the winner.
The Colonials (4-2) were held to 37.3 percent shooting from the floor, including 6-of-21 from 3-point territory.
Cordon Williams led Robert Morris with 19 points. Russell Johnson added 17 points and eight rebounds.