Duncan finished with 18 points on 7-of-13 from the field and 10 rebounds for San Antonio (48-14) and added five blocked shots. Manu Ginobili turned in a strong performance of his own with 18 points and nine rebounds, including 3-of-5 from the three-point line.
The Spurs shot well and made 54.1 percent of their overall looks and an outstanding 57.1 percent from the three-point line. They took care of the basketball on top of all that with only eight giveaways.
The Bulls struggled to get things going offensively and shot just 36.7 percent from the field.
Marco Belinelli led the way for the Bulls (34-27) 21 points on 8-of-16 shooting and added seven assists. Five Spurs players scored in double figures with at least 13 points.
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