The 'Jackets (5-6, 2-1 ODAC) broke open a tie game with a Lauren Seal goal at 22:06 and never looked back against SU (3-10, 0-5).
R-MC opened the game's scoring in the fourth minute, only to see the Hornets tie it at 18:00 when junior Sarah DeLuca converted a penalty stroke.
Macon got the Seal tally to take a 2-1 lead into the break and then converted a stroke goal of its own at the 44:38 mark.
Randolph-Macon outshot Shenandoah 18-6 and had nine of the game's 15 penalty corners.
Hornets goalkeeper Sarah Clare made 11 saves in the losing effort.
SU is back in action on Sunday at 2:00 against No. 15 Christopher Newport.