They never trailed, outscored the Raiders 27-9 during a 9½-minute span, held them to one field goal in 6½ minutes of the first half and extended their decade-long nonconference winning streak at Cameron Indoor Stadium to 80.
Yaw Gyawu scored nine points to lead Colgate (0-3), which was held to 31 percent shooting and turned it over 26 times.
Mike Krzyzewski earned victory No. 798 with the Blue Devils. They hit the 100-point mark for the first time this season and had little trouble winning their 13th straight game and 22nd in a row at Cameron.
And once again, their all-over-the-floor defense played a huge part.
Duke, which has won three home games in six days by an average of nearly 38 points, forced at least 20 turnovers for the second time and turned Colgate's miscues into 40 points.
The Blue Devils held the Raiders to 1-for-10 shooting during that cold stretch midway through the first half. Gyawu, who led Colgate by averaging 19 points in the first two games, finished just 4 of 14 from the field.
Irving and Smith had nine assists apiece for Duke, which coasted through one final breather before things get significantly tougher next week. The Blue Devils will play Marquette on Monday in the CBE Classic semifinals, will face either No. 11 Gonzaga or No. 3 Kansas State two nights later and later will play No. 2 Michigan State at home and No. 16 Butler in New Jersey.
Irving, the first freshman to start a season as Duke's point guard since Jason Williams in 1999, is looking quite comfortable running the show for the reigning national champions. He tossed up an alley-oop dunk to Ryan Kelly less than 10 seconds in, and the highlight-reel move during the game-breaking run was his double-clutch reverse layup that made it 31-17 with 8½ minutes left in the half.
His 3-pointer early in the half started the overwhelming burst that put this one well out of reach. Mason Plumlee capped that spurt with a free throw that made it 36-17 with 6:14 left. Duke made it a 20-point game with about one minute left in the half when Smith hit a reverse layup to stretch it to 44-24, and pushed the lead 30 on Smith's 3 with just under 16 minutes left.
By then, the Blue Devils were on their way toward improving to 14-0 against the Patriot League under Krzyzewski, who played for Bob Knight at Army and spent five years coaching there before coming to Duke in 1980.