The most significant fall-out from the 5-0 Ashes whitewash has been the strong suggestion that England are prepared to jettison Pietersen as they plan for a new era.
Cook fronted the media for the first time since those reports surfaced on Saturday - ostensibly to preview the one-day international series which begins in Melbourne on Sunday - but it was Pietersen's future that took centre stage.
The England skipper refused to be drawn on the subject though, which remains short on attributed detail so far.
That fact led to Cook to be probed from most angles on Pietersen, ranging from the South Africa-born right-hander's attitude in the dressing room to Cook's own relationship with him.
Cook, though, routinely stated that he was not prepared to provide any detail about whether Pietersen - or any other player - might face the axe until he has sat down after the ODI series to conduct a review with team director Andy Flower and the England and Wales Cricket Board (ECB).
"It's very hard for me to talk to you the media about this. It's very hard," the 29-year-old skipper said.
"I can't do that. Confidentiality and stuff like that - what happens in the dressing room stays in the dressing room."
Asked if that might be construed as a failure to endorse Pietersen, he replied: "You can regard it as you want. As is the way with the media that happens."
From Cook's perspective the way forward at the moment is clear.
His first task as captain is to lead England in a five-match series that will act as valuable preparation for next year's World Cup - which will be co-hosted by Australia.
Then, after the series finishes on January 26, he will fly home to begin the Ashes review.
"Now is not the time to be thinking about it," he said.
"We've done it, it's happened. I need to be fully focused now on trying to win this one-day series.
"I know you are going to drag me back there, I understand it, but we have to start focusing on the one-day cricket.
"That's my job and part of the multi-tasking.
"We know that when I get home from this one-day series a lot of important decisions on how we want to go forward with this Test team, the one-day team and my future - all that kind of stuff - is very important.
"My total focus has to be on us winning games of cricket in this series.
"We have a World Cup in 2015 in exactly the same conditions as we are going to experience here and that has to be given my full thought."
Cook was not always defiant, though - cracking jokes at times to lighten the mood - but he admits the failings of his side in the Ashes have weighed heavily on his mind since the whitewash was confirmed in Sydney a week ago.
"Obviously when you lose a series 5-0 a lot of things get thrown up and thrown in your face as a captain," he said.
"I would be wrong if I wasn't lying in my bed over the last week or so thinking about stuff I would like to do and how I would like to lead this side forward and the decisions which go with that.
"I think we need to change a lot of things. Maybe not a lot ... but this has been a real reality check, this Test series, for us."
Cook is glad that Flower will be alongside him to plot England's new path after the Zimbabwean, like the skipper, received backing from the ECB to stay in his job.
"He's a fantastic coach with a very good record," Cook said.
"It's important that he's got to really want to carry on.
"Seeing what he says in the media, he desperately wants to do that, so that's great news for us and we've got a lot of hard work ahead of us."
Cook is hopeful that the ODI series against Australia can kick-start any regeneration, with a host of young names potentially pushing their claims for the World Cup and Test team.
All-rounder Ben Stokes provided a shining example of a young player grabbing his opportunity - following his meteoric rise in the past six months - and Cook wants more of the same.
"It's an exciting time for a lot of these young players in this side," Cook said.
"They know they have a World Cup in a year's time. After seeing what has happened to the Test team they will be thinking there is a lot of places up for grabs in it.
"You saw Ben Stokes in the one-day series against Australia really put his name forward and suddenly he looked like he belonged in an international side.
"He forced his way in that way and was obviously one of our stand-out players in the Ashes.
"I know that those guys who are coming in - well I hope they know, they'd be pretty stupid if they don't know - that there are a lot of places up for grabs."