Langhurst scored 11 points and Chappell eight to help the Colonials take a 30-17 lead at halftime. Robert Morris led by as much as 53-37 after Josiah Whitehead converted the first two free throws of the game for the Colonials with 8:46 left to play.
Clarke's steal and subsequent 3-point play with 1:04 remaining capped an 11-3 scoring run that cut Robert Morris' lead to 61-55. Kashif Pratt's 3-pointer with 31.6 seconds left trimmed the edge to 64-59, but the Gaels got no closer.
The Colonials shot 64.9 percent from the field in the game to 40 percent for Iona.