Jaiswal scored IPL's fastest fifty, bringing up the milestone in 13 deliveries, and ended the innings with an unbeaten 98 off 47 balls. Earlier, Chahal (4-25) became the highest wicket-getter of the tournament, overtaking Dwayne Bravo.
Yashasvi Jaiswal continued his sensational run in the IPL by smashing the fastest fifty in tournament history after Yuzvendra Chahal became the all-time leading wicket-taker as Rajasthan Royals cruised to a nine-wicket win over Kolkata Knight Riders to resurrect their playoff hopes in Kolkata on Thursday. (More Cricket News) | (Scorecard)
Chahal became IPL's leading wicket-taker before completing a brilliant 4/25 as RR restricted KKR to a below-par 149/8 at the Eden Gardens
On a day KKR batters struggled to time the ball, 21-year-old Jaiswal showed the way by bringing up fastest fifty in the history of IPL in just 13 balls, bettering the previous record held by KL Rahul and Pat Cummins (14 balls each).
With the modest chase, Jaiswal remained two runs shy of a century (98 from 47 balls), a knock studded with 12 fours and five sixes as RR cantered to victory 13.1 overs.
Samson gave fine support to the southpaw with a 48 not out from 29 balls as the duo shared an unbroken match-winning partnership of 121 runs off just 69 balls.
The win with 41 balls to spare also took them to third spot (12 points from 12 matches), giving a massive boost to their net run-rate (0.0633) as the play-off race heats up.
It is all but over for KKR who slipped to seventh place (10 points, 12 matches).
Jaiswal made his intention clear in the first over itself when KKR skipper Nitish Rana made a bold move to bowl himself.
Wasting no time, Jaiswal seized on the opportunity and smashed Rana for two sixes and two fours in a row in a 26-run over.
He hit Shardul Thakur with a hat-trick of fours to race to his fifty in the third over itself as RR virtually sealed the issue scoring 78/1 inside powerplay.
To pile on the KKR misery, Sunil Narine dropped an easy catch when Samson was on 16.
The skipper then came on his own when he smoked Jharkhand left-arm spinner Anukul Roy for three sixes in a 20-run over.
On a day RR dished out an eye-grabbing fielding display, Chahal (187 wickets) eclipsed Dwayne Bravo (183) to become the all-time leading wicket-taker of the IPL when he struck off his second ball to dismiss KKR skipper Rana (22; 17b) in the 11th over.
Chahal's breakthrough came just when KKR looked to step up after a pathetic start when two astonishing catches of Shimron Hetmyer and Sandeep Sharma set the tone.
Both came in Trent Boult's successive overs as the Kiwi left-arm pacer returned with 2/15 from his three overs on his return.
After an expensive second over when he leaked 15 runs, Chahal came back in the death overs and dismissed KKR top-scorer Venkatesh Iyer (57; 42b) and Shardul Thakur (1) in four balls.
He ended his spell dismissing the latest KKR sensation Rinku Singh (16) in the penultimate over to also become the leading wicket-taker this season (21).
Put in on a dry Eden wicket, KKR frontline batters came a cropper, as Venkatesh held the fort and returned to form with a fighting fifty.
From being two off 12 balls, Venkatesh paced his innings well and raced to a 39-ball fifty. But he slashed a wide delivery from Chahal to be brilliantly caught by Boult.
Andre Russell (10) failed to make it big after he was promoted to No 5 and fell to KM Asif (1/34).
KKR, who were 58/2 after nine overs, looked to seize the momentum after taking a strategic time out in the 10th over.
Venkatesh finally broke free smashing Ashwin for back-to-back sixes, while Rana ended the over with an elegant four through extra-cover to take them to 76/2 at the midway mark.
KKR looked on course for a decent total before Chahal triggered a mid-innings collapse.