The last two reds, in particular, required a degree of accuracy and cue-ball control, both of which Mehta had in abundance.
The break finally ended when, after taking the last black and eyeing the maximum of 138 with only colours left, Mehta got snookered on the yellow with the cue-ball rolling behind the blue.
Merchant returned after a 30-minute break to win the sixth frame on the back of a run of 58 to reduce the leeway.
However, he was unable to take advantage of an opening in the seventh frame when Mehta played a poor safety shot that left his opponent on. Merchant crafted a 31 and a 21 for a 52-0 lead.
At this stage, a miss on the red presented Mehta an opening and the youngster went on to make 46 and then take the frame after Merchant gifted the final red in the centre pocket. Mehta cleared to pink to go 5-2 up.
Mehta effectively ended Merchant's challenge with a run of 43 at the start of the eighth frame. Merchant did have a chance to bounce back, but a miss on the black proved costly with Mehta swiftly making a 21 break to seal the issue.
MS Arun of Bangalore took home Rs.20,000 for the highest break (137) of the tournament while the losing semi-finalists, Sourav Kothari and Manan Chandra received Rs.25,000 apiece.
Former Davis Cup captain Ramesh Krishnan was the chief guest and gave away the prizes.
The results (final):
Aditya Mehta (PSPB) beat Yasin Merchant 6-2 (62-69, 59-01, 69-40, 111-00, 58-14, 12-80, 70-52, 72-13).