The freshman was 1-for-6 with three turnovers in the opening 20 minutes, but responded with 15 points in the second half as the Blue Devils (7-1) extended the nation's longest home winning streak to 32 games.
Princeton (4-3), playing its highest ranked team since 1997, trailed by eight points with 7_ minutes left before Deng scored on a driving layup to give Duke a double-digit lead.
Two minutes later, Deng hit a 3-pointer and his assist on a three-point play by Shelden Williams put Duke up 61-49 with 3:51 left.
Deng's only downer of the second half was a cramp in his left thigh that forced to leave in front of a cheering crowd with 2:38 left.
Andre Logan led the Tigers with 16 points.
Duke realized how much it missed a healthy Williams inside. He played just 19 minutes because of a sprained left ankle he reinjured against Portland three days ago, scoring five points.
With its offense struggling, Duke's defense was a factor again, forcing Princeton into a jump-shooting team in the second half by cutting off passing lanes.
After closing to 41-35 early in the second half, Princeton made just one basket over the next six minutes, missing four 3-pointers and turning it over four more times.
Princeton finished 2-for-18 from long range, missing all 12 attempts in the second half.
The Tigers fell behind by 10 midway through the first half and lost leading scorer Judson Wallace to foul trouble for more than 10 minutes, but used a 14-4 run to pull even with the Blue Devils.
Duke went more than seven minutes without a basket, going 0-for-8 from the field with four turnovers during Princeton's rally.
Redick's baseline jumper gave him 12 points for the half and Duke a slim 31-27 lead as the Blue Devils shot just 37 percent.