It was the team from Kolkata's second win in two matches over the defending champions, following their 11-run win in the tournament opener.
Ganguly hit nine fours and five sixes and added 78 runs for the fourth wicket with David Hussey (31) in a partnership that gave the Kolkata innings the solidity it needed.
He reached his second fifty of this edition with a huge six over long-on off Pragyan Ojha.
And in the left-arm spinner's final over, Ganguly went on the offensive, smashing three sixes.
He lost his wicket in pursuit of a fourth one, when was caught by Rohit Sharma at deep midwicket.
But by then the captain had done what he was supposed to do - lead his side from the front.
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