Perhaps coaches are the nemesis of Sourav Ganguly in his second part of cricket career - First Greg Chapell and now Gary Kirsten.
From a definite source it was heard that Indian cricket coach Gary Kirsten is the man who recommended Sourav Ganguly's ouster, that's according to media reports quoting one of the five selectors who made the decision to leave Ganguly out of the Irani Trophy. 
Perhaps the coach was not happy with Sourav at all but he could not do anything due to Sourav's sublime knock at home soil against SA. So the moment run dried up at Sourav's bat,Kirsten beheaded Sourav .
According to one of the selectors, post Sourav's failure in Sri lanka, Kirsten told the selectors it was time to look beyond Sourav, Anil Kumble apparently agreed, Sourav being a liability on the field too contributed to his being left out of the Rest of India squad.

Gary said we should look beyond. Even (Test and Rest of India captain) Anil Kumble shares that view. 

"Sourav hasn't been in form, plus he remains a liability on the field," the selector pointed out. 

Those close to Sourav now say he has achieved several milestones and is no longer as hungry as he was 2 years ago. So if he is left out of the Australia series he could well choose to call it a day.

Sourav Ganguly, however, brushed aside any such plans and said he thought himself to be good enough for at least a couple of years more.

"I would like to think I have a couple of years left," said Ganguly.