Up 71-58 with 2:30 left in regulation, the Columbia men looked well on their way to a comfortable victory at Levien Gymnasium, but Lehigh rode a huge 17-4 run to knot the game at 75 with seconds on the clock.
A controversial foul on the Mountain Hawks sent Lions junior guard Avery Brown to the line with 0.8 left, and the junior guard sank one of two free throws to seal the deal.
The relieved Lions are 4-0 for the first time since 2005, while a frustrated Lehigh sits at 0-3.