Having posted a modest 148 for nine in 20 overs, CSK bowlers led by Ashish Nehra (3/19 in four overs) and Dwayne Bravo (2/19 in 3.4 overs) exhibited brilliant death over skills to bundle out RCB for 124 in 19.4 overs.
Such was the dominance of CSK bowlers at the back end of the innings that RCB lost as many as seven wickets for 27 runs in only 5.5 overs.
From a relatively comfortable 97 for three with another52 runs to get, RCB's slump started when Bravo effected a superb reflex run-out off his own bowling to get rid of opposition skipper Virat Kohli (48, 44 balls).
Kohli had hit two fours and a six during his knock as he added 63 runs for the fourth wicket with Dinesh Karthik (23) after they were left tottering at 34 for three.
Once Kohli was gone, the procession started, with Karthik being snapped up in the deep off Nehra's bowling in the 15th over. In his very next over, the veteran seamer removed Safaraz Khan (8) and Harshal Patel (0) to take his wickets tally to 17 in the tournament.
Bravo, on his part, bowled an exceptional 18th over with clever change ups and the off-cutters which led to Mitchell Starc playing four dot balls.
On his part, skipper Mahendra Singh Dhoni read the pitch perfectly as he knew that it would slow down with passage of time and strokemaking would be extremely difficult in the second half. His intuition turned out to be spot on as his bowlers vindicated his decision.
Earlier, Mitchell Starc bowled brilliantly for his figures of 3/24 in four overs as RCB managed to restrict CSK to 148 for nine in stipulated 20 overs after Dhoni had decided on batting first. Starc was supported well by Harshal Patel (2/19) and David Wiese (2/29).
Suresh Raina, CSK's most consistent player over eight seasons, again top-scored with a 46-ball-52 that had five sweetly-timed boundaries apart from a six.
But Starc was the most impressive of the RCB bowlers as he first yorked Dwayne Smith (0) off the very first over that went for a maiden.
However, Brendon McCullum (20) was in his usual aggressive self as leg-spinner Yuzvendra Chahal and seamer Wiese came in for some harsh treatment during that initial period.
He raced to 20 but it was the pace of pitch that did him in as he tried to reach for a pull-shot and was caught at the mid-wicket boundary by Iqbal Abdullah off Wiese's bowling in the final over of the Powerplay.
Raina, who hit some delightful cover drives, then conjured a 64-run partnership with Faf du Plessis (24) as the pair took the team's total near 100 before Harshal's double blow put paid to the hopes of a big total.
First Du Plessis was played on and then off the last delivery, Raina was trapped plumb in-front trying to pull a length delivery.
Dhoni smashed 29 off 18 balls that had two huge sixes – one each off spin twins Abdullah and Chahal before being holed out in the deep.
Once Dhoni was gone, even 150 looked a distant dream as the 'Men in Yellow' finished two runs short of what seemed like a par-score on a slow Chepauk track.