Seaborn was 9 of 16 from the field with four 3-pointers. Collin Stewart scored 15 points and Justin Robinson added 14 points, six rebounds and four assists for the Hawks (12-4, 4-1 Metro Atlantic), who shot over 53 percent and made 12 of 24 3-point attempts.
Fairfield used a 14-5 run midway through the first half -including back-to-back 3-pointers from Cobb - to lead 47-40 at intermission.
Monmouth chipped away, and Seaborn's jumper 7 1/2 minutes into the second tied it at 56, and then he hit a 3-pointer on the next possession. That started a 16-5 run to put the Hawks up 71-61.
Fairfield got it to four a few minutes later, but made just one of its last five shots.