The visitors pulled off a stunning win after Chennai fell short of their 148 for six by nine runs. Kieron Pollard starred for Mumbai by smashing 57 off 38 balls and led their recovery from 83 for six in 12 overs.
Mahendra Singh Dhoni took his team's fight to the last over with an exhilarating 51 off 26 balls. But his dismissal in the first ball of the 20th over resulted in Chennai's loss in what was their first match of the tournament. It was a welcome result for Mumbai, who had lost a close contest against Royal Challengers Bangalore Thursday.
Chennai stumbled in the chase, losing half their side for 66. But with dangerous Dhoni and Ravindra Jadeja in the middle, you could still not rule out the hosts getting the required 83 runs off 47 balls.
With Jadeja back in the hut on 16, the onus was once again on Dhoni to take the team home. The skipper hit an array of lusty blows to take the match down to the wire. Chennai needed 23 off the last 12 balls after Pollard bowled a 17-run over.
Mitchell Johnson came to bowl the 19th over and Dhoni did not spare him too. He brought his fifty with a cracking six over deep mid wicket, cutting the target to six off the final over with two wickets in hand.
With Dhoni in full flow, it seemed the massive crowd in attendance for the opening IPL game here would get their money's worth. All of that changed one when Pollard pulled off a stunning catch at the boundary to dismiss Dhoni.
Earlier, Mumbai Indians were off to a bad start after winning the toss, losing the 'dream' opening combination of Sachin Tendulkar and Ricky Ponting (6) for 17.
The master blaster was adjudged leg before wicket off pacer Dirk Nannes on the first ball he faced. Apparently, he was not happy with the umpire's decision.
The ball was doing a bit and Dhoni used his faster bowlers for the first nine overs. The ploy paid off as wickets kept on falling at regular intervals.
Besides Pollard's power hitting, the innings also saw Dinesh Karthik (37) continuing with the form he displayed in Bangalore Thursday. The wicket-keeper looked set for his second fifty in a row before he fell to Dwayne Bravo, making it 59 for four.
Two more got out quickly leaving Pollard and Harbhajan Singh in the middle.
The West Indian expectedly scored the bulk of the runs in their 65-run stand, made exciting with his five sixes and four boundaries. Harbhajan played his part well by scoring run a ball 21.