This was the first hat-trick of the ongoing 9th edition of the league.
Invited to bat by Gujarat Lions skipper Suresh Raina, Kings XI Punjab were all out for 154 in the stipulated 20 overs, but restricted the opposition to 131 for 9 in front of their home crowd at the Saurashtra Cricket Association Stadium.
Appointed captain midway into the cash-rich tournament in place of David Miller, Murali Vijay led from the front with a fluent knock of 55.
Patel then spun a web around the Gujarat batsmen and finished with impressive figures of 4/21 in his quota of four overs which included a split hat-trick.
With this win, Kings XI Punjab finally managed to turn things around in what has been a nightmarish campaign so far.
Kings XI Punjab now have four points with two wins and five defeats from seven matches, while the Lions, despite the reverse, stayed at the top with six victories and two losses from eight appearances.
Chasing a modest target, the Lions were off to a poor start, losing the dangerous Brendon McCullum (1) with just 13 runs on the board in the second over. Raina was the next to go, being bowled by medium pacer Mohit Sharma, who also accounted for the wicket of McCullum in a similar fashion. Raina made 18 off 15 balls, hitting a couple of boundaries and a six.
Patel then took centrestage as the 22-year-old slow grabbed the wicket of opener Dwayne Smith (15) with his third delivery.
He then snared Dinesh Karthik and Dwayne Bravo off successive balls - fifth and sixth of the seventh over. Patel returned to pick the wicket of Ravindra Jadeja with the first delivery of the 11th over to complete the split hat-trick.
After sending back Bravo, Patel celebrated by performing the West Indian's 'Champion' jig.
Owing to the flurry of wickets, Gujarat Lions were reeling at 39 for five, which soon became 57 for six in the 11th over.
The chase was as good as over but Ishan Kishan (27), James Faulkner (32) and Praveen Kumar (15) delayed the inevitable by playing out the full quota of overs. Even as the lower-order wagged, Gujarat Lions' top batsmen including the likes of McCullum, Raina and Smith failed miserably. Mohit Sharma (3/32) complemented Patel well.
Earlier, Vijay led by example during his 41-ball knock, hitting six boundaries. He shared 65 runs for the opening wicket with Marcus Stoinis (27). The Australian scored his runs off 17 balls and struck three boundaries and a six.
David Miller (31) and wicketkeeper Wriddhiman Shah (33 not out) shared 39 runs for the sixth wicket to take the visitors past 150. While Miller found the fence two times during his 27-ball knock, Saha blazed away to 33 off just 19 balls while striking four boundaries.
As far Gujarat Lions' bowling is concerned, left-arm spinner Shivil Kasuhik, whose action has an uncanny resemblance with former Proteas left-arm spinner Paul Adams returned figures of 3/20, while there were two wickets apiece for Praveen Kumar and Bravo.
Brief Scores
Kings XI Punjab: 154 all out in 19.5 overs (Murali Vijay 55; Shivil Kaushik 3/20).
Gujarat Lions: 131 for 9 in 20 overs (James Faulkner 32; Axar Patel 4/21, Mohit Sharma 3/32).
KXIP beat Gujarat Lions by 23 runs.