Branden Frazier added 16 points for the Rams, who snapped a 10-game losing streak and won at St. Bonaventure for the first time since Jan. 28, 2009.
Fordham (7-24, 3-13 Atlantic 10) trailed 41-35 at the break but opened the second half on a 20-5 run to go up 55-46 with 12:35 left. St. Bonaventure responded with a 17-4 run to jump back on top, 63-59, with 6:48 showing.
Jermaine Myers hit a 3-pointer on the Fordham's next possession, sparking 12 straight points for the Rams. Gaston scored seven during the spurt as Fordham led from there.
The Bonnies (14-15, 7-9) shot 46 percent (23 of 50) but hit 9 of 27 3-pointers.
Purdue coach Matt Painter says players haven't used the fifth-year graduate transfer rule for its true intent.
The dust has settled after players made their NBA draft decisions. Which college teams won? Which lost? Well, Villanova is pretty happy. USC, meanwhile, might not be as thrilled.
The 2017 recruiting class is short on point guards, with Trevon Duval leading only eight prospects from the ESPN 60 who are still available.