The talismanic skipper's couple of monstrous sixes in his 9-ball-20 did help CSK get to 167 for 8, which was at least 20 runs above-par on a tacky Chepauk track.
The total was just what Dhoni needed to marshall his bowlers as Delhi Capitals were never in hunt after their batting mainstays David Warner (0), Phil Salt (17) and Mitch Marsh (5) were out by the start of the fourth over.
In the end, DC managed only 140 for 8 and their struggles were real as not even 10 fours were hit in the entire innings. The DC batters managed only seven boundaries and four over-boundaries.
The win took CSK to 15 points and one win from two remaining games will certainly seal their place in the last four. As far as DC's campaign is concerned, it is almost curtains with 8 points from 11 games with seven defeats.
Before one points fingers at head coach Ricky Ponting and Director of Cricket Sourav Ganguly, there would some of the talent scouts, who should be held accountable for presenting the team with options who are incapable of being x-factors even at the domestic level.
A former India player's son, who is one of the talent scouts, will have a lot of answering to do.
The Indian batters like Manish Pandey, Ripal Patel, Lalit Yadav or Aman Khan aren't good enough to ace easy chases on their own leave alone getting better of tough targets like this one on the day.
The two veterans Ravindra Jadeja (1/19 in 4 overs) and Moeen Ali (0/16 in 4 overs) tightened the noose around the DC batters in the middle overs when Pandey and Rillee Rossouw added 59 at less than run-a-ball.
Pandey, especially after running Marsh out could have done better, but in his 16 seasons of IPL, he hasn't even won 10 games for all the franchises that he played.
Matheesha Pathirana (3/37 in 4 overs) nailed his yorker perfectly to send the former India player packing.
Earlier Capitals bowlers came to the fore, keeping the Super Kings batters on the leash on a sluggish pitch before Dhoni and Ravindra Jadeja (21 off 16 balls) put pressure on DC bowlers at the back-end.
None of the CSK batters could go on and get a substantial score with Shivam Dube (25) being the highest score. There were 20s by Ruturaj Gaikwad (24), Ambati Rayudu (23) and Ajinkya Rahane (21).
Electing to bat after skipper Dhoni won the toss, the home team was pegged back by some fine bowling by the Capitals bowlers, especially left-arm spinner Axar Patel (2/27). Mitchell Marsh (3/18 ) was the best bowler while Kuldeep Yadav (1/28) and Lalit Yadav (1/34) were the other wicket-takers.
The big-hitting Dube smacked the first six of the innings, hoisting Axar Patel into the stands in the 11th over. He hit two more before a pull of Mitchell Marsh landed in the hands of skipper David Warner.
He made 25 (12 balls) and helped increase the CSK scoring rate which had been slowed down due to some good bowling.
The second over bowled by Ishant Sharma yielded 16 runs as Gaikwad hit three boundaries
In the third over, Conway swished at a delivery from Khaleel and the bowler seemed to think he heard a nick. However, the Capitals didn't review it and later the replays showed a faint edge.
Conway, however, did not make much of the 'life' as he was trapped LBW by Axar Patel for 10.
At the end of the powerplay, CSK were 49 for 1.
Gaikwad was dismissed trying to up the pace, caught in the deep as Axar Patel continued to stymie the Super Kings.
Moeen Ali could not force the pace and was sent back by another spinner-Kuldeep Yadav- caught in an attempt to reach out and play a shot.
There was no six hit by the CSK batters in the first 10 overs as the Capitals bowlers sought to put the squeeze on run-scoring.
Ajinkya Rahane's innings was cut short on 21 when Lalit Yadav took a superb return catch.