The Thoroughbreds had a tough time solving SLU's Aaron Marshall, who finished with 29 points, 14 rebounds, three blocks and four steals.
Dana Martin led the Thoroughbreds with 26 points, including five threes. J.P. Corry added 16 points, while Cortlandt Toczlowski added 13.
Skidmore (15-8, 9-5 Liberty League) will be the second seed in the Liberty League Tournament. The Thoroughbreds will face Hamilton in the semifinals on Friday at Hobart.