TVNZ boss Ross Dagan fielded calls from potential replacements within hours of Bagust's on-air announcement today that she would leave the show when it ends for the year on December 21.
"I would imagine we would be inundated with people expressing interest, for sure. I've had a few this morning already," said Dagan, the network's head of news and current affairs.
"But today's about Petra's announcement and her decision and we need to allow that to unfold and we'll turn our attention to the chair away from today."
During her announcement Bagust thanked the Breakfast team for their efforts during her two years on the show, which she said had been "bloody hard work".
She referenced the Christchurch earthquake, Japan's quake and tsunami, the Royal Wedding, the Rugby World Cup and Olympics as highlights.
"It's been a rollercoaster ride. Bring on summer and 2013."
Dagan was unwilling to speculate on who might step into Bagust's shoes next year.
But media insider Martin Gillman said it wouldn't matter - the popular programme survived Paul Henry's exit and wouldn't lose viewers with Bagust's exit.
"There will be someone good who will replace her, I have absolutely no doubt at all. [But] the presenter doesn't make the audience," said Gillman, a partner at Mitchener Gillman Communications.
"TVNZ keep a very close track on the viewer popularity of all their presenters. I don't know where Petra would have featured on there."
Dagan said today had been "quite emotional" for Bagust and the team.
"She did a really great job to hold it together on air. I think behind the scenes she's been certainly emotional leading up to telling the team this morning," he said.
Dagan said the exiting host was "keen to sleep in past 3.50am and spend more time with her young family".
Candidates to fill Petra Bagust's seat at Breakfast?
- Breakfast reporter Toni Street may take a promotion upon her return from maternity leave
- TVNZ business reporter Nadine Chalmers-Ross is no stranger to Breakfast
- Rachel Smalley could consider the jump from TV3's Firstline
- TV3 reporter Samantha Hayes may be interested in a fulltime presenting job
- Paul Henry's former co-host Pippa Wetzell was a favourite on Breakfast
- By Kieran Campbell of APNZ
