Big names have roamed between the worlds, and a few exist in the middle - spies with brilliant disguises.

Mick Malthouse crossed over, but just for a little while.

Collingwood supplied Mick with retirement. The black-and-white tiles under his feet cracked and broke away. The decision was made above him and around him.

So he wandered out - passing the growing flowers, singing birds and a restful life - and went straight into the media. Signing on with the Channel Seven and 3AW footy teams, the famously irritable Malthouse, who had little patience for those media types and their bloody silly questions, found himself smiling into the camera and asking a few questions of his own.

But before his freshly printed press pass had the chance to curl at the ends, he swapped it for a Carlton jumper and a ''coach'' car park.

Just what did Malthouse get out of his big adventure with the cameras, microphones and make-up? Did it change his view of the hungry and squawking media?

Not likely.

''The easiest thing is to be a critic,'' he says. ''Negativity flows out of most people. Coaching is about being positive.''

Not long after his radio career started, there was enough negativity to change his whole season. In April 2012, the premiership coach got pecked by the sharp Magpie beak of Eddie McGuire.

Malthouse thought he was doing his new job when he leaned into a microphone and commented on the game plan of new coach Nathan Buckley. The Pies had just been belted by Carlton, and Malthouse described their defence as ''leaky''. The Collingwood president grabbed his own day-job mike and showed some defence, media-style. ''I love Mick and I've supported him 100 per cent, but I tell you, he wouldn't have a friend at Collingwood today,'' McGuire said, and added, ''Give Bucks a go, mate,'' as though Malthouse should have been showing a blood-oath loyalty to McGuire's coach.

Any love McGuire has for Malthouse is silent. The two have not talked for more than 12 months. Their words are for the rest of Melbourne to hear. ''I've always believed in friendships,'' Malthouse says. The one with McGuire seems over for all time.

But the McGuire swoop was effective. Malthouse decided he was done talking about his old team, telling Seven and 3AW he no longer wanted to cover Collingwood games.

Even in footy terms, Malthouse has an emotional verve that's unique. He has the sporting passion of Chariots of Fire and the personal sentimentality of E.T.

Emotion is the wood burning in the Malthouse boiler. It can be used to drive a productive engine, but it has been known to build up and shake - jetting steam and causing frightening squealing sounds. But that's him.

''I'm sometimes a victim of that emotion,'' Malthouse says about his successful curse. ''That is probably one of the overriding things that takes over. And you're quick to defend your family, your team or your club. At times, I didn't control them. Maybe that's what makes me a football coach.''

And never is emotion more a factor than the post-game press conference. It's there that Malthouse has been his most cross-armed with raw crankiness. ''I used to get annoyed 15 minutes after a win or a loss. I could always tell who journos barracked for. I still think there are a lot of old ones [journalists] that have an agenda,'' Malthouse says, adding that many had agendas for ''other people''.

''I've tried to be as professional as I can. And I know sometimes I've failed,'' he says, copping some of the blame. But with little hope of a softer, marshmallow-type Malthouse following a 2013 Blues loss, what about the future of sports reporting?

During his wilderness year Malthouse went back to school, mentoring students at La Trobe University, including undergraduates in journalism. ''I'll be judging the young media people coming through,'' he says, hoping he did something to lift the standard.

Before I got the chance to spend time with Malthouse at 3AW, I thought he was a bit of a sook towards the media. But I came to enjoy our chats and loved the passion-charged, bungy-jump style conversations you could have with him. And with all his chest-out confidence comes some naivety that's hard not to like.

But I could see a change in him once the new job was announced. He was a coach again, on his guard. Just a little.

So, Mick Malthouse went from closed up to candid, and then back again. He's returned to a life of balls, boys and grassy battles.

Perhaps it was meant to be this way - the old ''agenda'' journos ramming their questions and Emotional Mick always protecting, like he was guarding a treasure map.

Imagine a press conference - minutes after the opposition's team song - if Malthouse welcomed us with tea and cakes, and all the answers. It just wouldn't feel like our game. The worlds are now aligned, once more.

Justin Smith is a presenter and senior producer on radio 3AW.