Humbert raced to a 3-0 lead in the first set of the Australian Open warm-up event before Paire staged a comeback to force a tie-breaker.
Rising 21-year-old Humbert regained the upper hand to take a 1-0 lead but looked nervy in the second set, allowing Paire to draw level.
Paire looked jaded in the decider, having played five three-setters throughout the week, but refused to throw in the towel when Humbert served for the championship at 5-3.
Paire fired three consecutive backhand winners and went on to force another tie-break before Humbert finally sealed victory to ensure he will jump inside the top 45 for the first time on Monday.
(Reporting by Amlan Chakraborty in New Delhi; editing by Peter Rutherford)