New Zealand's Devon Conway and Ruturaj Gaikwad smashed half-centuries to fire Chennai Super Kings into the IPL play-offs with a thumping 77-run win over Delhi Capitals on Saturday.

The left-handed Conway (87) and Gaikwad (79) put on a blazing opening stand of 141 to steer Chennai to a mammoth 223-3 after electing to bat first in Delhi.

Skipper David Warner hit a valiant 86 but Chennai kept down Delhi, who are coached by Ricky Ponting, to 146-9 and book their spot in the top four.

They join holders and table-toppers Gujarat Titans, who are assured of a top-two finish.

Four-time winners Chennai have finished the group stage with eight wins and can stay as the second-ranked team in the table, depending on the day's second result between Kolkata Knight Riders and Lucknow Super Giants.

The season remains special for Chennai skipper M.S. Dhoni, who is believed to be playing his last season and has attracted huge crowds wearing the teams' yellow as a tribute to the legendary cricketer.

Dhoni, 41, though has kept the fans guessing and still not clarified on his swansong.

Delhi, who were the first team to get eliminated from the play-off race, bowed out with nine losses and five wins.

Batsmen set up victory for Chennai after Gaikwad and Conway, in his 52-ball blitz, got cracking on the opposition bowlers with fours and sixes.

Chetan Sakariya sent back Gaikwad, who hit seven sixes in his 50-ball knock, but Conway kept up the charge in another attacking partnership of 54 with Shivam Dube, who hit 22.

Dube's wicket raised the noise as Dhoni walked in with thunderous applause and stood unbeaten with Ravindra Jadeja, who hit a seven-ball 20.

Delhi were never in the chase as Warner played a lone hand in his attempt to drive the teams' reply in his 58-ball knock but got little support from the other end.

Pace spearhead Deepak Chahar took three wickets while Sri Lankan duo of Matheesha Pathirana (fast bowler) and Maheesh Theekshana (off-spinner) took two each.