Chennai Super Kings registered a thrilling six-wicket win over Royal Challengers Bangalore in the play-off to enter the final of the Indian Premier League in Mumbai, on Tuesday.

Chasing a tough target (176), the defending champions romped home with two balls to spare.

Virat Kohli struck a superb unbeaten 70 off only 44 deliveries to lift Royal Challengers Bangalore to an imposing 175 for 4 in their 20 overs.

Kohli began slowly and then accelerated towards the end of the innings, hammering three sixes and five fours, as RCB made light of a rare failure by Chris Gayle to set a stiff target for Chennai, who need to score at 8.8 runs per over for victory.

Apart from Kohli, opener Mayank Agarwal scored 34 off 33 balls, with five fours, and Luke Pomersbach made a quick-fire 29 off only 18 balls to give the innings the much-needed impetus when it was needed.

For the Super Kings, left-arm pacer Doug Bollinger emerged the pick of the bowlers with one for 20 while off-spinner Ravichandran Ashwin, who dismissed Gayle cheaply in his first spell, finished with one for 33.

Dwayne Bravo and Albie Morkel were off-target, the latter conceding 40 runs in his four wicketless overs, while Shadab Jakati picked one for 37.

The Chennai Super Kings were off to a disastrous start, losing openers Michael Hussey and Murali Vijay with only seven on the board.

Both were trapped leg before -- Hussey by Zaheer Khan, with a ball that came in, and Vijay by Sreenath Aravind.

Subramaniam Badrinath, on nine, offered Kohli a return catch which the bowler did not accept and then Raina, on 14, was caught at fine leg off the same bowler only for it to be declared a waist-high no-ball.

Kohli was hit for 16 runs in the over as Badrinath took full advantage of two full tosses, which he dispatched to the ropes to help the Super Kings reach 50 in the ninth over.

Badrinath was dismissed, caught in the deep covers off Abhimanyu Mithun after adding 63 runs for the third wicket with Raina.

Suresh Raina smashed an unbeaten 73 from just 50 balls, hitting four fours and six sixes, to help Chennai from an impossible position.

The left-hander showed great composure in the closing overs despite the mounting run rate to win the match for his team with two balls to spare.

The defending champions looked set for a defeat till they exploded in the end as they smashed 67 runs from the last 28 balls.

Raina admitted that this was one of his best innings in the IPL.

"God has been really kind to me. I made 94 not out against the RCB in the Champions League. The wicket was totally different then. This was my best effort. It's important to finish in an IPL match. When the team needs you, especially in quarter-finals, semi-finals and final, you have to deliver and I am happy I have done that," he said.

Captain Mahendra Singh Dhoni joined Raina, who carted Mithun for two sixes in the 13th over before his captain struck the last ball, a free hit, for another four. The over cost 23 runs, and at the end of it the Super Kings were six short of 100.

They needed 58 off the last four overs but it came down when Raina swung Zaheer for two sixes while Dhoni swatted him over long-on for another maximum.

The over, which also saw the dismissal of Dhoni, cost the team 20 runs.

Albie Morkel came out all guns blazing, hitting 28 not out from just 10 balls to leave Bangalore stunned.

He put on 46 runs, in just three overs, for the fifth wicket with Raina.

Needing 12 off the last over, bowled by rival skipper Daniel Vettori, Morkel swung him for a four and a six to complete the task.

Chennai Super Kings now have a chance to defend their title against either Bangalore, or the winner of the eliminator between Mumbai Indians and Kolkata Knight Riders.

Bangalore have a second chance, playing the winner of the eliminator in the second play-off in Chennai on Saturday. 

Raina believes though Chennai will start as favourites in the IPL final to be played on their home ground, it will not be an easy task to repeat their achievement from last year.

"It is very important to execute your plan. Everyone is going to expect us to win the final. It is important to do your process well. We may be playing on our home ground, but the final is a different game. You have to do well in each and every department of the game," he said.