"Got plans to revitalize it, they'll look at different ways of doing things. I'm not part of those plans and I wish them well in what they're going to do.''
Mr Sainsbury said he will be spending more time in Wellington - as he has been commuting from there to Auckland for the past six years.
Ralston - a longtime friend of Sainsbury - predicted Close Up would be replaced by a soft magazine style show "more like Breakfast.''
Telegenic TV host Pippa Wetzell has been tipped for a bigger role in TVNZ.
And Ralston suggested TVNZ bring back New York news correspondent Jack Tame to front the new show. A media industry source said New Zealand's Got Talent host Tamati Coffey has also been mentioned in dispatches.
Ralston said TVNZ's proposed "re-formatting'' of the show meant there would no longer be an attempt at serious current affairs.
Ralston said the changes marked a culture in TVNZ management that objected to the significant budgets for news and current affairs and the costs securing ratings.
The demise of Sainsbury's Close Up has been debated for months, and the change tipped by nzherald.co.nz on July 27.
One view of events suggested to the Herald was that head of news and current affairs Ross Dagan had accepted the need for change to the weeknight format, which harks back to the days of Holmes.
Dagan said the proposed changes were being made as a response to viewer feedback.
"Close Up remains the number one daily current affairs show by a substantial margin, but ratings for us and for our competitors in this important time slot have diminished over time," he said.
"We're committed to staying at the forefront of what New Zealanders want to see and we owe it to them and to ourselves to continually evolve and enhance television current affairs.
"We want to reinvent the early evening slot, to present the stories of the day in a way that is very different to what has gone before."
A Facebook post by TVNZ asked viewers what kind of current affairs show they'd like to see in the 7pm slot. The first reply suggested, "One with Paul Henry in it," while the second said, "One without Mark Sainsbury".
Dagan said Close Up's format had "run its course".
"Everyone on the show is aware that traditional current affairs formats are losing favour with audiences, and this team has set the bar for what's possible. However despite the efforts of a group of very talented people, and a degree of success, the company's view is that this format has simply run its course.
He praised Sainsbury's performance over the past few years.
"As presenter Mark Sainsbury has done a fine job and has earned a deserved place in television history through his coverage of some of the most significant issues in New Zealand's recent past."
Close Up has been running for nearly eight years and runs in direct competition to TV3's Campbell Live. Last night's episode was the fourth most-watched show on TV with 474,000 viewers, Throng.co.nz reported. Campbell Live had 283,210 viewers.
Details about the proposed revamp weren't released, but staff were being consulted with an outcome due in mid-October.
- additional reporting nzherald.co.nz
