Sunil Narine smashed the joint fastest IPL fifty in his sensational knock of 54 as Kolkata Knight Riders thrashed a hapless Royal Challengers Bangalore by six wickets to seal a playoffs berth here on Sunday.

Narine (54 from 17 balls) reached his fifty in just 15 balls, the same number of deliveries his KKR teammate Yusuf Pathan had consumed in 2014 against Sunrisers Hyderabad, as he played some stunning shots much to the disappointment of the home crowd at the Chinnaswamy Stadium.

The West Indian and his opening partner Chris Lynn (50 from 22 balls) put on 105 runs from just 6.1 overs in a show of batting pyrotechnics as KKR chased down the target of 159 in a jiffy. They romped home with 4.5 overs to spare.

Yuzvendra Chahal (4-0-39-1), Sreenath Aravind (1-0-26-0) and Samuel Badree (3-0-40-0) bore the brunt of the fury from Narine and Lynn. The KKR batting duo also notched up the record of the highest powerplay total in the IPL as the visiting side were 105 for no loss at the end of six overs.

The win, their eighth of the season, sealed KKR a play- offs berth with 16 points from 12 matches. Already out of reckoning, RCB, on the other hand, slumped to their 10th defeat in 13 matches to remain at the bottom of league table with mere five points.

It was Lynn who began the carnage as he hit Aniket Choudhary for two fours and a six in the first over. He continued in the same vein by smashing another six and two fours in the third over bowled by Yuzvendra Chahal.

Narine took over after that. The first two deliveries Narine faced were dot balls but he sent the home crowd to a stunning silence in the fourth over by hitting three successive sixes and a four to cream off 25 runs from Badree.

The next over was even more stunning and the hapless bowler was Aravind as a ruthless Narine sent him for four boundaries and a six to take 26 runs and raised his fifty.

Lynn then took over and picked Chahal for the special treatment as he took 20 runs from the bowler with a four and two sixes to notch up the record of most runs in powerplay.

Narine got out immediately after that and Lynn followed suit in the next over but by then irreparable damage had been done on RCB as KKR were on course for an easy win.

Colin de Grandhomme (31) and captain Gautam Gambhir (14) took KKR on the threshold of victory before Manish Pandey (4 not out) completed the formalities as KKR reached 159 for four in 15.1 overs.

Earlier, Travis Head smashed a brilliant unbeaten 75 after Mandeep Singh's 52 as RCB recovered from a top-order collapse to post 158 for six after being put into bat.

The big names like Chris Gayle, Virat Kohli and A B de Villiers were dismissed cheaply as RCB slumped to 34 for three in the fifth over. Mandeep (52) and Head then stitched 71 runs for the fourth wicket to take the score past 150-run mark.

Head hit two sixes and a four from the final three deliveries as RCB took 21 runs in a late flourish.

Mandeep hit four boundaries and a six in his 43-ball knock while Head struck three fours and five sixes in his 47-ball unbeaten knock.

The match began in a dramatic fashion with Gayle, who has failed miserably this season, getting out in the first ball bowled by Umesh Yadav. The West Indian tried to defend but the ball moved away and took a leading edge to land at the hands of KKR captain Gautam Gambhir at short cover.

In comes Kohli and the India captain negotiated six deliveries for two runs before he was dropped by Piyush Chawla off the bowling of Yadav in the third over.

Kohli (5), who has struggled this season, did not take advantage of the dropped catch and was out the next ball with Yadav having the last laugh. The change of pace did the trick as Kohli was beaten by Yadav's delivery to be out LBW.

Mandeep, on the other hand, hit some lusty blows at the other end, including a six off Chris Woakes, but another wicket — in the form of de Villiers — fell in fifth over.

De Villiers, who also had a season to forget, hit a four off Sunil Narine but in the next ball, he was out clean-bowled while trying to play a sweep shot of a fullish delivery.

With their best three batsmen gone for a meagre score, RCB reached 63 for three at the halfway stage with Mandeep and Head holding fort.

The duo batted through a rain-forced break of over 30 minutes with Mandeep reaching to his fifty shortly after resumption. But he got out immediately after reaching his fifty in the 16th over before Head took the score to 158 for 6 with some late big hitting.