Jonathan Simpkin's reliability as a substitute and his seasoned body have allowed the 25-year-old to fulfil a boyhood dream and write the most memorable chapter of a football career that has taken twists and turns to Saturday's grand final at the MCG.

It is understood Hawthorn felt the more mature Simpkin was the safer choice to fill the role of substitute for the showdown against Fremantle, putting him ahead of draftee Jed Anderson, 19, who was thought to be the front-runner to clinch the spot vacated by injured teammate Brendan Whitecross.

What a story. @jsimpkin32 well done mate. After being @ sydney & geelong when they won their flags he now gets his chance to play in one

— Brendan Whitecross (@BrendanWhiteX) September 26, 2013

While the Hawks felt the younger and quicker Anderson might have had more impact, it is understood the coaching staff decided Simpkin's bigger body would be the better option to hold up over an entire game should the Hawks lose a player to injury early.

Simpkin, Anderson and four other players in contention were reportedly called to a meeting about 2pm on Thursday and told one would walk away satisfied, and the others dejected.

For the Colac-raised Simpkin, the good news caps a life-changing week for the midfielder, after he won the medal for best on ground in Box Hill's VFL grand final win against Geelong on Sunday. The Cats cut him from their list this time last year.

Simpkin, who has not played for Hawthorn's senior team since round 20, has had to do it the hard way, having signed on as a delisted free agent with the Hawks after being the unlucky casualty of Geelong's rookie-list squeeze.

Before that, he had been cut from Sydney's list two seasons after being drafted as a rookie for 2006 and then elevated to the main list in 2007.

It was only four years ago that Simpkin was playing suburban football for his junior club Colac in the Geelong Football League, and told close friends that he feared his AFL chance had passed him by.

Those who knew him well said he had a choice to make - continue to knock around playing local footy with his schoolmates, or have one more crack with Geelong's VFL team.

Come Saturday, Simpkin - whose brother Tom plays for StKilda - could receive the ultimate pay-off should he and fellow Colac boy, Luke Hodge share a premiership with the Hawks.

Simpkin has the best record of any Hawthorn player coming out of the green vest, having averaged 11.5 disposals in the six matches he has played as the substitute.

On every occasion he has come on after half-time, with his 18-disposal effort against the Brisbane Lions in round 14 - which also included four inside-50s and a goal - standing as one of his best performances.

Simpkin, who has played 13 games this season, is one of only four Hawks who have not played in a grand final before, the others being Brian Lake, Bradley Hill and Max Bailey.

Fremantle has only two players, Zac Dawson (with St Kilda) and Danyle Pearce (Port Adelaide), with grand final experience.

Simpkin was the only change to either side, with the Dockers as expected naming key defender Luke McPharlin and forward Chris Mayne.

Both players trained away from the main group at Thursday's final training session before the team flew out from Perth.

McPharlin, along with All-Australian defender Michael Johnson, have been nursing calf injuries all week, and Mayne has a back compliant, but all three are expected to play.

There were no last-minute shocks for the Hawks, either, as Lance Franklin, who hurt his elbow last week, and Paul Puopolo, who has been bothered by a slight ankle issue, were both named.