Garnett also hauled down 18 rebounds and Jason Terry contributed a key 3-pointer in the final extra period to finish with 26 points for the Celtics, who have yet to fall since all-star guard Rajon Rondo was lost for the season to knee surgery.
Ty Lawson had in 29 points and nine assists for the Nuggets, whose nine-game winning streak came to an end in the marathon loss.
Denver also got 18 points and 10 rebounds from Danilo Gallinari and 14 points with 12 rebounds from Kenneth Faried.
2014: NFL Cheerleaders [PHOTOS]
Michael Sam cut from the Dallas Cowboys