Next month the ICC is due to confirm changes to the governance of the game, and take power back from the Big Three.
The alterations were agreed in principle last month by a 7-2 majority -- India and Sri Lanka against, Zimbabwe abstaining.
India need four votes to turn the proposal back and scupper the two-thirds majority required next month.
They have recently met officials from Sri Lanka, Zimbabwe and Bangladesh, and announced an ODI series involving at least two of those teams. Draw your own conclusions.
Manohar, an Indian who previously headed the Indian board, has been critical of their manoeuvring, calling them "not always in the best interests of the game".
He pushed for a more equitable model, and his proposed changes will see the BCCI's income from a new television rights deal fall from about US$450 million to about $290 million -- still the largest chunk of revenue, but that's small consolation to the money-hungry Indian board.
India aren't happy. Their cricket administration is in chaos, the board suspended by India's Supreme Court and its affairs in the hands of four disparate, but respected figures -- a former auditor general of India, an eminent historian, the managing director of India's largest stock exchange and a former captain of India's women's team.
Last month, the ICC talked of introducing a rolling two-year test championship and World Cup qualification through a three-year cycle of ODI cricket. New plans are to be ratified next month. Manohar's departure puts a giant question mark over that.
When his resignation letter reached ICC chief executive Dave Richardson on Wednesday night (NZT) it was of jaw-dropping, "he's done what?" magnitude.
There is talk that Manohar had agreed a small increase on the initial reduction on the proposed revenue share to India. He's reported to have been in good spirits. Then the bombshell a day later.
"It was a total surprise," New Zealand Cricket's chairman Greg Barclay said. "I thought everything was tracking well and he gave every indication of being comfortable in his role."
So what happened? No one seems to know but mutterings are afoot that in some way Manohar was nobbled.
Countries were quick to jump on the Big Three takeover in 2014 as a good thing, afraid of standing up to, in particular, the financial muscle of India, so they can't be trusted not to take that path again next month.
One prominent cricket voice, Sambit Bal of ESPNcricinfo, has contended that if the reforms go ahead it could be a return to the days when the "BCCI was outside the tent growling and ready to strike".
Much good planning could fall under the bus if countries opt not to press on with the reforms. In that sense, Manohar's departure shapes as potentially a dark day for the governance of the game.