Wagner's Aaren Edmead made two free throws to tie the score at 31 one minute into the second half. Monmouth responded with a 9-1 run to take the lead.
The Seahawks climbed within four points five different times, and made one final push for a comeback on a three-point play, closing to 65-62 with 2:18 to go. Monmouth went 5 of 6 from the line to end it.
Monmouth shot 52.1 percent overall, while the Seahawks finished at 32.8 percent.
Romone Saunders led the Seahawks (2-7) with 18 points, scoring 10 of those in the first half.