Iona hit 54 percent from the floor, including 13 of 27 from beyond the arc. Leading scorer Sean Armand was held to just 11 points.
Siena (7-12, 3-5 Metro Atlantic) trailed by six points midway through the second half when A.J. English's layup kicked-off an 11-2 Iona run capped by a Williams layup giving the Gaels a 70-57 lead with seven minutes to play.
Tavon Sledge's basket inside the paint extended Iona's lead to 17 with 4:40 left, marking the largest lead of the game. The Gaels coasted to the buzzer, winning by 14 points.
Iona (9-8, 6-2) also beat Siena last Sunday 87-78, and has won seven of its past eight meetings.
After a season that saw his shooting numbers slip, should Nigel Hayes return for his senior year at Wisconsin or take the gamble to put him name in this year's NBA draft?
Isaiah Taylor talks about his decision to declare for the NBA draft and what he will miss most about Texas.
Chattanooga women's basketball coach Jim Foster has received a one-year contract extension, the same day the school gave the men's coach a two-year extension.