The Rajasthan victory now sees them on equal points with both Mumbai Indians (4) and Kolkata Knight Riders (5); each side with three games remaining.
Chasing 177 to win, Buttler got off to an absolute flier in the powerplay as he put on 48-runs for the opening wicket with new partner - Ben Stokes - who was opening for the first time in T20s.
Rahane and Samson have been average while the inconsistent run of Ben Stokes has affected their performance this season.
The train with 14 coaches was on its way to Pune to facilitate the fans watch the cricket match slated for Sunday (May 13) when their favourite CSK team will take on the Sunrisers Hyderabad (SRH) team. Gowtham hit another six in the same over to take RR close before falling in the last ball of the penultimate over. For Rajasthan, Archer bagged two wickets for 42 runs while Sodhi scalped one conceding 29 runs. Stuart Binny departed for 22 off 17 balls, hitting a four and a six as Buttler continued to fight on at the other end.
Buttler would smash a six off the fourth ball of the final over and score the winning runs with one ball to spare.
Chennai Super Kings were at their dominant best as the spin duo of Harbhajan Singh and Ravindra Jadeja wrecked havoc on the RCB batting line-up.
Till the third over of the RR innings, Stokes had scored just a single run while Buttler had struck 32 off 15 deliveries.
Sanju Samson (21) was run-out after a awful mix-up while debutant Prashant Chopra (8) hit a couple of boundaries before failing to pick a slower from Shardul. Change of colour of jerseys may not help RR's plans in controlling CSK's rampaging opener Shane Watson (who hit a century when the last time the two teams met) who appears to be keen to do very well against the team he once captained.
After Raina's departure, Chennai was at 119/3 in 13 overs. Leg-spinner Ish Sodhi (1/29 in 4 overs) was impressive once again. Raina and Watson easily read the slow deliveries, even the googlies, and kept the scores ticking for CSK.
Raina started by clipping Archer off his pads to the square leg boundary. In the same over, he got his second four with a square drive. And then with two needed off two, Buttler cut the ball to cover point and collected the two more - courtesy overthrows - to seal Royals' fifth win in 11 games. Farm he did, but he also found the boundary on six of those 12 balls, and raced away to 27 off 12. Watson then pulled a short one by Jaydev Unadkat over the deep midwicket region. However, it was Butter's day. Sanju Samson (21) did give Buttler some support from the other end but was guilty of ball-watching as he was run out at a crucial point in the match.