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Mumbai Indians posted an imposing 202 for five as skipper Rohit Sharma (50) and Lendl Simmons (68) rattled up a 119-run stand off just from 67 balls after being invited to bat.
The Mumbai captain, who has an ODI world record of 264 and also a debut Test hundred at the Eden Gardens, yet again exploded at his favourite venue.
Sharma (6 fours, 2 sixes) and Simmons (8 fours 3 sixes) plundered 19 boundaries in their partnership.
Mumbai bowlers complimented the good work of the batsmen as they took the fizz out of the Chennai's chase with a very disciplined effort.
They straitjacketed the Chennai batsmen, restricting them to 161 for eight as seasoned spinner Harbhajan Singh took key wickets of Dwayne Smith (57) and Suresh Raina (28) in two overs.
Kiwi paceman Mitchell McClenaghan (3/25) took three wickets while his Lankan pace colleague Lasaith Malinga (2/25) scalped two batsmen.
Mumbai had won their first title in 2013 at this very venue, defeating the same rivals. Chennai have now lost four finals (2008, 2012, 2013, 2015) in six appearances.
Chasing the huge target, CSK opted to have it easy and concentrated on building a platform after losing Michael Hussey (4) early.
Smith and Raina bided their time and looked to consolidate but it meant that they managed only 31 runs from the first six overs. The required run-rate kept on going up and shot past 13 at the midway mark.
Smith completed his half-century in 45 balls but only to be trapped lbw by Harbhajan in his penultimate over. Having made a grand comeback into the Bangladesh-bound Test side, Harbhajan completed his spell in style dismissing Raina.
Looking to step out, Raina was brilliantly deceived by the veteran off-spinner who bowled a wide ball and Parthiv Patel did the rest behind the stumps.
With Hussey, Smith and Raina back in pavilion, and skipper Dhoni not looking in his usual elements it looked as good as over for the yellow brigade who choked in an IPL final for a fourth time.
Talk about Sharma and his sizzling love-affair at Eden Gardens, and he has done nothing wrong here. A stunning 177 on Test debut, an ODI world record of mindboggling 264, an IPL century (60-ball 109) against Kolkata Knight Riders and an unbeaten 98 in the opening match of this season.
