The Maroons (10-1, 3-0 ODAC) earned the one-goal win, their seventh over SU (7-5, 1-1) in 16 lifetime meetings, by scoring the final two goals of the game.
Roanoke refused to fold its tents, however, knotting the game at 2-2 barely four minutes after Hayes' goal and then getting the game-winner with 4:16 to play.
SU had one more shot on goal, by Raven Barter in the 66th minute, but was not able to bring the game back to level.
The Maroons took 15 of the game's 26 shots and had a 6-2 advantage in penalty corners.
Hornets goalkeeper Isabella Morande made seven saves.