Shenandoah (22-8, 8-4 USA South) secures sole possession of second place in the league with the victory over the Captains (25-5, 9-3).
The win is also the 400th of the career for SU skipper Kevin Anderson. Anderson is now 400-216-1 in a combined 13 seasons at Shenandoah and James Madison.
Victory No. 400 might have been the last in a long line of wins, but it was far from easy.
Leading 8-3 with two outs in the ninth after freshman Matt Riegler retired two of the first three, the doors nearly completely came off for the Hornets.
Christopher Newport saw seven consecutive men reach base and had the bases loaded when Anderson turned to Jeff Stanek to try and end the threat.
Stanek, the fourth SU reliever of the frame, got catcher Ben Lenda looking on a 3-2 pitch to end the game and give the Hornets the one-run victory.
The Shenandoah win snaps a nine-game winning streak for Christopher Newport.
Senior Cory Nelson (4-3) allowed three runs (just one earned) on six hits and three walks in 7 2/3 innings.
Jacob Vaughn (4-1) took the loss. He allowed six runs on eight hits in 2.0 innings.