The Saints led 40-37 at halftime before Rider used a 16-9 run to go up 53-49 when Fred Scott buried a 3-pointer with 14:58 left.
Rider extended its lead to 70-61 nine minutes later when Scott and Siena's Gary Harris Jr. became entangled in a scramble for a loose ball. The two tumbled to the ground, a confrontation ensued and they were promptly ejected. Rider assistant coach Geoff Arnold also was ejected.
The play triggered a 10-2 run by the Saints, and Jordan King's 3 with 1:35 left reduced their deficit to 72-71 but they never got closer.
The Broncs (8-4, 2-0 Metro Atlantic Athletic Conference) made 15 of 18 from the foul line to seal it in the last 1:24. Rider finished 28 of 33 (84.8%) from the foul line.
Scott scored 11 before his ejection.
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