Murali Vijay and Wriddhiman Saha scored half-centuries as Kings XI Punjab dealt Mumbai Indians' Indian Premier League play-off ambitions a severe blow, winning by seven wickets.
Last year's champions sit level on points with Delhi Daredevils and Kolkata Knight Riders - third and fourth respectively - but have now played two more matches than their two closest rivals for a top-four finish as the regular season nears its conclusion.
The Indians failed to hit their stride with the bat, put to the sword by the in-form Marcus Stoinis (4-15) as they toiled to 124-9.
And Vijay (54 not out) and Saha (56) inspired lowly Kings XI to a comfortable victory in Visakhapatnam, chasing down their target with 18 balls to spare.
Unmukt Chand and Ambati Rayudu both went for ducks as the Indians' innings got off to a poor start, and they were 45-3 at the midway point.
Contributions of 27 and 25 by Kieron Pollard and Nitish Rana were as good as it got for the Indians, with both men seen off by Stoinis, who also claimed the wickets of Jos Buttler (9) and Krunal Pandya (19).
Kings XI came into the match amid reports Shaun Marsh had been sent home because of a brawl with a team-mate - claims refuted by Glenn Maxwell in the build-up.
And the visitors showed no sign of disharmony as Vijay and Saha worked together to build a partnership of 116 runs, after Hashim Amla had been removed for nought at the end of the first over.
Maxwell's contribution matched that of Amla after Saha was bowled by Mitchell McClenaghan (2-24), but Gurkeerat Singh's four over mid-on saw Kings XI over the line in convincing fashion.