The Bluejays won their second straight after losing two in a row and pulled even with Wichita State at the top of the Missouri Valley Conference.
McDermott added 10 rebounds and paced Creighton to a 15-of-28 effort from beyond the arc. Ethan Wragge added 15 points for Creighton (19-3, 8-2 MVC).
It was the fifth loss in six games for Missouri State (6-16, 4-6). Drew Wilson led the Bears with 19 points.