Rosenberg was 6 of 7 from the field and 17 of 17 from the free-throw line. His only miss came from 3-point range where he was 2 for 3.
Columbia (18-10, 7-4 Ivy League) extended a 33-30 halftime lead to 72-54 on Steve Frankoski's 3-pointer with 6:31 left. From there Maodo Lo hit a pair of free throws with 3:13 left and Rosenberg made 10 in the final 2:08 for the Lions to easily hold on.
Lo had 16 points with seven assists and four 3-pointers. Frankoski had four 3s with 14 points, and Meiko Lyles scored 10.
Tyler Melville was 4 of 5 from 3-point range, leading Dartmouth (9-16, 2-9) with 19 points. Connor Boehm added 17 points, and Brandon McDonnell and Alex Mitola each scored 10.