Vermont trailed through most of the second half but three consecutive layups by Lamb rallied the Catamounts (7-3) to a 59-57 lead with 4:11 to play. They stretched it to 66-62 on an Ernie Duncan layup with 1:06 left and held on in the final seconds for the win.
Lamb was 14 of 22 from the field, including five from distance. Duncan added 14 points and six assists.
The Catamounts led by two with 4:47 left in the first half when Harvard’s Corey Johnson sank three 3-pointers and Spencer Freedman nailed a fourth to help push the Crimson into a 36-29 lead at the break.
Johnson scored 17 points with five rebounds to lead the Crimson (4-5).