McDermott provided 16 points and seven rebounds while Manigat contributed 13 points and five assists as the Bluejays (15-1, 4-0 MVC) reeled off their ninth straight win.
Creighton also got 10 points, five boards and four assists from Grant Gibbs in the triumph.
The Bulldogs (6-9, 0-4) were paced by Joey King with 17 points.
Micah Mason and Jordan Clarke each added 11 in the loss.
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