Colin Nickerson added 13 points to go with four steals and Derek Needham had 12 points for Fairfield.
Rider (6-5, 1-1 Metro Atlantic Athletic Conference) led by as much as 11, 26-15, in the first half before Fairfield used a 17-4 run over the final 4 minutes to cut the deficit to 32-29 at intermission. The Broncs missed their first six second-half shots and Fairfield capitalized, taking a 45-34 lead before Rider’s first bucket of the frame.
Fairfield (5-5, 1-1) led by at least six the rest of the way.
The Stags forced 29 turnovers, on the strength of 19 steals, and held Rider’s leading scorers Anthony Myles and Nurideen Lindsey to a combined 0-for-9 from the field with 10 turnovers.