After 159 games the premiership defender sensed he needed to add another dance step to his routine to maintain his effectiveness and increase the team's versatility.
Once the idea was agreed to in principle O'Brien set himself the task of improving his fitness to allow him to play in positions outside the back 50.
He began with a pre-season training regime that was more demanding than he had endured in recent seasons.
Harder training saw O'Brien maintain muscle mass while his skinfold measurement – never a problem in any case – decreased. The need for a combination of strength and power was also emphasised.
Leaner, without being meaner, would probably be the best description you could apply to the modified O'Brien.
On Sunday against West Coast, early indications were that O'Brien could become an exciting option for the Pies on the re-emerging wing position.
He prowled the Subiaco Oval wing, pushing forward to snap at goals, setting up a wall across the centre, and rebounding quicker than a ping-pong player with the wind behind him.
As an audition for a new role, it was worth a round of applause.
"It is something we have worked pretty hard on throughout this pre-season," O'Brien told AFL.com.au.
Nothing is fixed, however. The work has been about making O'Brien even more valuable.
"It's not so much that I'll be playing as a permanent wingman," O'Brien said. "I guess it's to add to my flexibility."
O'Brien knows he can adapt.
He began as a free-running defensive player but came to the fore when he successfully locked down key opposition forwards such as former Bomber Scott Lucas.
He then became a premiership and All-Australian defender.
This latest move just represents another stage in his career.
"I've always been able to play on a range of opponents but now to be able to push up the wing adds another string to my bow," O'Brien said.
The time is right, too.
Not because of the perception O'Brien can no longer beat an opponent. That's a school of thought he doesn't pay much attention to.
"I am aware and the coaching staff are aware of what my strengths and limitations are," O'Brien said.
The timing is spot-on because whenever an opponent got the upper hand on him last year – inevitable for any defender – there seemed few release valves in place.
At times he looked like a DJ in a dance crowd with a case full of golden oldies.
Now the Magpies are bursting with runners out of defence, with O'Brien, Ben Johnson, Heath Shaw and the rapidly emerging Paul Seedsman all capable of playing dual running/defending roles.
The chance to switch and swap and confound is rapidly developing as Collingwood creates a mash-up of defenders and wingmen around the defensive edge of the midfield.
"It's a huge advantage that we haven't had in previous years," O'Brien said. "We have got a lot of depth at the moment and it is a really good position to be in. So the more we can have players being developed in different roles [the better]."
Heritier O'Brien is a defender in NAB AFL Fantasy. He averaged 62.14 points in 2012. Register your team at our AFL Fantasy Hub.
Peter Ryan covers Collingwood and Melbourne news for AFL.com.au. Follow him on Twitter at @AFL_petryan
