Chennai coasted to a seven-wicket win over Mumbai to make it three wins on the spin in this season's Indian Premier League.
Seamer Mohit Sharma claimed 4-14, including three wickets in his final over, to restrict the Indians to 141-7, a total that the Super Kings comfortably surpassed with six balls to spare.
Brendon McCullum led the run chase for Chennai, the opener making an unbeaten 71 from 53 deliveries, including two sixes and eight fours.
The New Zealand skipper shared in a 57-run stand with Dwayne Smith, who hit four sixes in his 29, and then added a further 53 with Faf du Plessis (20) after Suresh Raina had fallen cheaply.
Harbhajan Singh had Raina stumped for just a single and then combined again with wicketkeeper Chidhambaram Gautam to dismiss Du Plessis, though at 114-3 the Super Kings were well on course for victory.
Captain Mahendra Singh Dhoni hit a six and a four in an unbeaten 14 that saw his team home. They now sit level with the unbeaten King's XI Punjab at the top of the table on six points.
Mumbai, in contrast, prop up the eight-team league having lost for a third straight outing in the seventh year of the competition.
Rohit Sharma top scored with 50 in their innings; the India international put on a third-wicket partnership worth 84 with New Zealander Corey Anderson before the latter was run out for 39 off 31 deliveries.
At 123-3, the Indians looked set to post a challenging target for their opponents, only to lose their way dramatically once Sharma hit Ben Hilfenhaus to Smith in the deep.
An out-of-sorts Kieron Pollard was bowled by Sharma during a stunning 19th over that also saw Ambati Rayudu and Harbhajan both fall to catches. Having begun the over on 125-4, the Indians ended it struggling at 127-7.
Zaheer Khan did manage a late six off Hilfenhaus but they never looked to have enough on the scoreboard to defend, even with Lasith Malinga in Mumbai's attack. The Sri Lankan paceman sent down four wicketless overs at a cost of 22 runs, Chennai knowing they had to take few risks against him.