Siraj's impressive swing bowling saw Kolkata's innings fold tamely at 8-84. Only England captain Eoin Morgan showed some resistance with a top score of 30.

Kolkata's batting performance was only slightly better than their lowest-ever IPL score - 67 against Mumbai Indians in 2008.

Siraj became the first bowler in IPL history to bowl two maiden overs in a single game and, at one stage, his figures read 2-2-0-3 before he conceded eight runs in his final two overs.

Bangalore eased to 85-2, knocking off the runs with more than six overs to spare despite losing both openers -- Australian Aaron Finch (25) and Devdutt Padikkal (16) -- in the seventh over.

"Last year Siraj had a tough year and a lot of people went hard at him," Bangalore skipper Virat Kohli, who finished off the run chase, said.

"This year he has worked hard and was bowling well in the nets. He has seen the results now, but we want him to keep following the process."

Delhi Capitals and Bangalore now occupy the top two slots with 14 points each after winning seven of their 10 games. Kolkata are fourth with 10 points after losing their fifth game.

"Being four or five down as early as we were is disappointing," Morgan said, adding that he should have bowled first instead of opting to bat after winning the toss.

However, even Kohli admitted it had been a good toss to lose because he would have batted first too.

Kolkata's frontline batsmen had no answer for Siraj's swing with the new ball as Rahul Tripathi was caught behind off his third delivery and Nitish Rana followed off the next ball, clean bowled.

Australian Associated Press