Invited to bat, Mandeep cracked a strokeful 75 off 48 balls to help Punjab post a challenging 170 for five in their stipulated 20 overs. The visitors then returned to restrict the Chargers to 145 for eight to keep their hopes alive of reaching the play-off stage by reaching the fifth position in the IPL points table.
Chasing 171 to win, opener Daniel Harris (30) gave Deccan some hope initially but they failed to build partnerships and kept losing wickets in regular intervals.
For Punjab, Praveen Kumar, Parvinder Awana and David Hussey took two wickets each to emerge as the peak of the bowlers. They were supported well by Azhar Mahmood (0/31) and Piyush Chawla (1/33).
The chargers had a tottering start as they lost inform opener Shikhar Dhawan (8) and first down Parthiv Patel (17) cheaply to slip to 31 for two in the first five overs.
In the seventh over, Harris picked up a six off the first ball by Chawla and Cameron White played an inside-out shot in the last delivery to end the over with a boundary. In the next over, Harris picked up a four off Ramesh Powar at the square leg area before whacking one at the mid-wicket area for another boundary.
Punjab then tightened things up with seamers Awana and Mahmood giving away just four and two runs in the next two over respectively. However, it was skipper David Hussey who broke Deccan`s backbone, striking twice in four balls in his only over to dismiss the two set batsmen - Harris and White - and reduce Deccan to 71 for four.
In his first ball, Hussey had Harris caught at point and three balls later, danger man White holed out to Shaun Marsh at wide long-on. A lot was expected of skipper Kumar Sangakkara but all that the Sri Lankan could do is edge Praveen`s second delivery to keeper Nitin Saini.
With Deccan looking down the barrel at 74-5, Abhishek Jhunjhunwala (19) and Akshath Reddy (24) took them to 100 in 15.2 overs. But with the required runrate increasing all the time, the batsmen perished in search of boundaries.
Akshath holed out to Marsh off Awana, while Jhunjhunwala paid for his lazy running between the wicket and was runout by at least a couple of yards. Earlier, Mandeep blasted eight fours and three sixes to set the foundation for a big score for the Kings XI. He stitched 55 runs for the opening wicket, before adding 39 and 33 runs with Hussey and Mahmood respectively.
The 20-year-old opener started the proceedings for Punjab on a cautious note before blasting two fours and a six in the second over off Veer Pratap Singh.
Other opener Shaun Marsh also picked up three boundaries spread over two overs off Rusty Theron before being dismissed by part-time spinner Shikhar Dhawan. Dhawan deceived Marsh on the flight as the ball deflected off the pads onto the stumps.
Ashish Reddy then dismissed Nitin Saini in his first over to reduce Punjab to 58-2 in 7.4 overs. However, Mandeep hit the last ball over wide long-on.
Amit Mishra was then introduced into the attack but skipper David Hussey sent him sailing over extra over only in his second ball. Mandeep too ensured that runs keep coming thick and fast and brought up his fifty with a lofty inside out shot off Daniel Harris over cover.
Veer then got rid of Hussey when he had him caught at long-off. But Mandeep was unperturbed and blasted successive fours off Mishra through the midwicket area to bring up the hundred for Punjab.
In the 15th over, Mandeep took Veer to the cleaners. He first slammed a six over fine-leg and then one ball later, scooped one over the bowler`s head. Ashish finally got rid of the opener when he had his off-stump pegged back in the next over while he was looking for a big slog.
Azhar Mahmood then clubbed a couple of fours before falling prey to a big mix-up in the 17th over. However, new man David Miller (28) provided the late charge, smashing three fours and a six in his 18-ball cameo to swell the total.