Kieron Pollard blasted 87 not out from 34 balls as Mumbai Indians completed a stunning chase of 219 against the Chennai Super Kings on the final ball.
The West Indian came in with 138 needed from 62 balls and hit eight sixes and six fours for a four-wicket win.
Mumbai needed 16 from the final over - and Pollard, dropped two overs earlier on 68, hit a six, two fours and scampered a two from the last ball.
It was the second highest chase in Indian Premier League history.
England all-rounder Moeen Ali had earlier hit 58 from 36 balls before Ambati Rayudu blasted a 27-ball 72 to lift top-of-the-table Chennai to 218-4.
"Probably one of the best T20 games I have ever been part of," Mumbai captain Rohit Sharma said.
"I have never seen a chase like that before. One of the best innings, also, from Polly."
Pollard said: "I was chomping to get in to see if I could hit a couple of sixes off the spinners firstly and then take it from there.
"I only got two overs against spin and I had to maximise that over against Jadeja."
Defending champions Mumbai stay fourth after the win but now have eight points, two fewer than Chennai, Royal Challengers Bangalore and Delhi Capitals.