Morehead State (5-1) scored the first five points and never trailed. Treshaad Williams and Anthony Elechi had four points apiece in a 16-2 run to end the first half, capped by a 3-pointer from Corban Collins, that left Morehead State ahead 38-15.
Saint Louis outscored Morehead State 22-11 over the first 15 minutes of the second half to get within 12 at 49-37. Xavier Moon scored a pair of baskets in a 7-0 run to build the lead back to 19 with three minutes remaining.
The Billikens, who made 16 3-pointers over their two previous games, made just 1 of 9 on Wednesday.
The Eagles are off to their best start since 1990-91 season.