Put in, Knight Riders recovered from a poor start, and crucial innings from Manoj Tiwari (41), Gautam Gambhir (27) and Yusuf Pathan (21 not out) helped them achieve a modest total of 140 for seven in 20 overs.
Tight bowling by the Knight Riders and a mesmerizing spell of spin bowling by West Indian Sunil Narine (four for 15) helped his team bowl out Mumbai for a paltry 108.
Jacques Kallis (2-32) too played a key role as he removed Kieron Pollard and Dwayne Smith off successive balls to put Kolkata in the driving seat. Lakshmipathy Balaji also picked up two wickets giving away just 11 runs from his four overs.
In Image: Kolkata Knight Riders' Gautam Gambhir, right, and L. Balaji celebrate after their win
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