The Broncs (20-10, 14-5) clinched the No. 2 seed in the Metro Atlantic Athletic Conference Tournament.
Okereafor and Lundy scored 14 points to start the second half for an eight-point advantage. Rider continued to lead by the same margin with 2:53 remaining, but Justin Robinson scored five-straight points to pull Monmouth within 58-56 with just under 2 minutes to play.
Rider went 5 of 8 at the line at the end to stay in front, Okereafor finishing with 21 points and Lundy with 17. The Broncs were without leading scorer Matt Lopez, who is out for the rest of the season with a torn ACL.
Robinson scored 15 points to lead the Hawks (16-14, 12-7).