Rohit Sharma hit his first IPL fifty of the season Mumbai Indians inflicted a rare home defeat on Chennai Super Kings by 48 runs.
Chennai missed MS Dhoni and Ravindra Jadeja due to illness as they failed to achieve their target of 156.
Shane Watson was out early after facing just five balls as Chennai crashed to 109 all out in 17.4 overs. It was Chennai’s first defeat at their Chepauk stadium since May 2015 when Mumbai also came out on top.
A victory would have ensured a spot in the top four for Chennai.
Sharma (67 off 48) anchored his side's innings, while veteran Sri Lanka bowler Lasith Malinga took 4-37 off less than four overs.
Spinner Krunal Pandya also bowled brilliantly for his two wickets for seven runs off three overs.
"We had to scrap for every run and every wicket, you can't ask for much more," said Sharma after the game.
Sharma said Dhoni's illness had been a "massive boost" for his side.
"His presence does a lot for their team. When you don't have Dhoni when they're chasing the score, then it becomes difficult for them."
Mumbai, after a poor start to the season, are now second in the table and like Chennai need just one win from three games to book a place in the playoffs.