Mumbai Indians are famed for their batting line up but came up short against the Delhi Capitals bowling attack, led by Amit Mishra.
Opting to bat, Mumbai lost opener, Quinton De Kock, early, who edged a Marcus Stoinis delivery to Pant in the third over.
Suryakumar Yadav then joined Rohit Sharma and the pair rallied the innings with their 58-run stand.
Yadav hit successive fours off Amit Mishra as Mumbai raced to 55 for one after six overs.
However, Delhi pegged back the defending champions by grabbing three quick wickets.
Avesh Khan struck the first blow dismissing Yadav, who nicked one to Pant and then Mishra removed Rohit and Hardik Pandya for a duck as Mumbai slipped to 77 for 4.
Mumbai then lost half its side for 81 as Krunal Pandya chopped an under-cutting arm ball by Lalit Yadav onto his stumps.
Mishra then used his famed googly to trap Kieron Pollard lbw for just 2 with the score at 84 for six.
Finally, a 26 from Ishan Kishan, who became Mishra’s fourth wicket, coupled with Jayant Yadav’s 23 took Mumbai to 137 for 9.
Sweet revenge for Delhi
Leg-spinner Amit Mishra’s four-wicket haul coupled with a crucial 45 by opener Shikhar Dhawan laid the foundation for Delhi Capitals’ six-wicket win.
It was Delhi’s first win over MI in last five meetings, having lost four times last season in UAE.
Chasing 138 to win, Delhi lost opener Prithvi Shaw for 7 runs as he gave a return catch to Jayant Yadav who ended with figures of 1/25.
Dhawan, who started with a cut short for a boundary, was joined by Steve Smith who made 33.
The two resurrected the innings by adding 53 runs for the second wicket.
Smith, who hammered two fours off Krunal Pandya in the 9th over, was the aggressor but a lapse in concentration against Kieron Pollard trapped him leg before wicket in the 10th over.
However, Dhawan kept going and smashed five fours and one six in his 45 and forged a solid partnership with Lalit Yadav (22 not out) which kept Delhi in the reckoning.
Dhawan perished in the 15th over with the score at 100 when Krunal Pandya taking a diving catch in the deep off Rahul Chahar.
Captain Rishabh Pant fell cheaply for 7 runs but West Indian Shimron Hetmyer (14 not out) and Lalit Yadav played sensibly to take Delhi home.
Delhi Capitals 138 for 4 (Dhawan 45, Smith 33, Pollard 1-9) beat Mumbai Indians 137 for 9 (Rohit 44, Mishra 4-24, Avesh 2-15) by six wickets