After DePaul had pulled to within one point at 59-58 with 7:36 remaining, McDermott keyed a 14-2 run that sent the Bluejays (19-3, 9-1 Big East) to a 13th straight home win and four consecutive victory overall.
McDermott, who collected his 1,000th career field goal in the game, and went 13-of-14 from the free throw line and also grabbed nine rebounds.
The Blue Demons (10-14, 2-9) were led by Brandon Young with 16 points.
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