AB de Villiers is next in line with 192 maximums. Behind de Villiers is Chennai captain MS Dhoni, whose count stands at 187.
R Ashwin-led Punjab, playing at home, registered second win of the season.
Quinton de Kock scored 60 off 39 balls and crossed the 1000-run mark in the cash-rich league.
Mumbai have retained the same playing XI which beat Bangalore in their previous game.
Kings XI Punjab 174 for 6 in 20 overs [Chris Gayle 50 (40), Marcus Stoinis 29 (15)*; Jasprit Bumrah 4-0-19-1] lost to Mumbai Indians 176 for 4 in 19 overs [Suryakumar Yadav 57 (42)*; Krunal Pandya 31 (12)*; Mujeeb Ur Rahman 4-0-37-2] by 6 wickets.
With this win over KXIP, MI move to No.5 in the IPL 2018 points table.
Mumbai and Punjab have squared off 20 times in IPL with both winning 10 matches each.
Guptill first played a breezy knock at the top and then plucked a stunner-of-a-catch of Simmons to turn the tide in his side’s favour.
Match 51 of the ongoing Indian Premier League (IPL) 2017 saw 453 runs being scored in 40 overs at Wankhede Stadium in Mumbai.
With everything to play for, Kings XI Punjab defeated the likes of Kolkata Knight Riders (KKR) and Mumbai Indians (MI) in their last two games and are on the brink of a playoff berth.