After electing to field first, Kolkata started the innings with Nitish Rana taking the new ball. His first ball was driven by Mumbai skipper Rohit Sharma for a creamy drive through extra cover. It was an indication of what was to come in the power-play.
Sharma went after Varun Chakravarthy, taking him for consecutive fours in the fourth over. Quinton de Kock slammed a six over fine leg against Lockie Ferguson before slamming Prasidh Krishna for back-to-back sixes in the final over of the power-play.
De Kock continued to be the aggressor in the opening partnership with consecutive fours off Andre Russell's first two balls of the night. Sunil Narine broke the partnership at 78 as Sharma (33) miscued a slog-sweep to long-on. It was the ninth time Narine dismissed Sharma in T20s.
Narine and Chakravarthy stemmed the flow of boundaries in three overs after Sharma's dismissal. Krishna, after conceding 16 in his opening over, came back to dismiss Suryakumar Yadav (5) edging behind to keeper Dinesh Karthik.
De Kock went slow in middle overs but managed to reach his half-century in 37 balls. But the pressure of going big forced de Kock (55) to hoick a slower ball off Krishna straight to mid-wicket.
Ishan Kishan (14) pulled Andre Russell for a six over fine leg. But in a bid to go big, Kishan again went for the pull off Ferguson, only for top-edge to be caught by Russell running from long-on.
Kieron Pollard smacked Krishna for a pull over deep mid-wicket before bottom edge on another pull ran through fine leg in the 18th over which went for 18 runs, including a no-ball and two wides. Pollard's attempt to apply finishing touches ended in a run-out by a throw from Morgan at cover in Ferguson's final over.
One brought two for Kolkata as Krunal Pandya (12) mistimed to long-on. Ferguson's final over went for just six runs as Kolkata were able to keep Mumbai under 160.
Brief scores: Mumbai Indians 155/6 in 20 overs (Quinton de Kock 55, Rohit Sharma 33, Lockie Ferguson 2/27, Prasidh Krishna 2/43) against Kolkata Knight Riders.