Gill hit 6 of 7 from 3-point range and picked up his first double-double. Jeremiah Jones scored a career-high 20 points. Derrick Colter, making five 3-pointers, had 19 points with nine rebounds. Micah Mason added 13 points for the Dukes, who made 34 of 64 shots for 53.1 percent, including 16 of 31 from 3-point range.
UMBC scored 17 straight points spanning halftime to cut a 28-point deficit to 11, 53-42. But the Dukes' kept their double-figures lead and led by as many as 21 in the second half.
The Dukes (7-2) are 5-0 at home and off to their best start since opening 7-2 in 1979-80.