Manny Camper made 1 of 2 free throws with 36.8 seconds left to give Siena a 58-57 lead. On its ensuing possession, Rider had one shot block and missed two others. Kadeem Smithen made 1 of 2 free throws for Siena with 4.6 seconds left before Jordan Allen's 3-point try went off the glass as time ran out.
Smithen had 16 points and six rebounds for Siena (13-12, 8-4 Metro Atlantic Athletic Conference), which earned its fourth consecutive win. Jalen Pickett added six assists. Camper had nine rebounds.
Rider scored 25 points in the second half, a season low for the team.
Siena takes on Iona at home on Wednesday. Rider plays Quinnipiac on the road on Tuesday.