Rookie-listed by the Hawks for the 2009 season - the same year the likes of Jordan Lisle, Shane Savage, Ryan Schoenmakers, Liam Shiels and Luke Breust arrived at the club - the former Sydneysider has had to work hard to make up the ground he lost growing up in a non-AFL heartland.
But if his elevation to Hawthorn's senior list last week is any guide, Sierakowski's persistence is paying off.
"I was a fair way back when I was first rookie-listed," Sierakowski told hawthornfc.com.au.
"The comp I played in in Sydney isn't great, and I was injured most of my under-18s year, so I only got a couple of games at state level.
"So I had a lot of exposure to bad football, which sort of set me behind the pace a little bit, and I was also a little bit immature in the strength department."
Two-and-a-half years on, Sierakowski - whose journey with the Hawks started when he was selected as one of their inaugural NSW scholarship players at age 16 - is on the cusp of a senior debut.
He travelled to Launceston with the team as an emergency for last Saturday's win over Gold Coast, and is listed as first emergency for Friday night’s big clash with Essendon.
The 20-year-old says the success of others from his draft year, particularly fellow New South Welshman and rookie Breust, has given him confidence he can compete at the top level if the opportunity presents.
"I lived with 'Breusty' for a year, so it's good to see him getting a go, and it's shown that the young boys at Hawthorn are ready to go and can really contribute," Sierakowski said.
"It hopefully gives the coaching staff confidence in the younger players, and it gives you a feeling that if they can do it, I can do it as well."
Hawks development coach David Flood believes a chance on the big stage would be fair reward for a player who has shown immense dedication since arriving at Waverley.
"He's had to work his way through and learn his craft, and he's still got a way to go, but he's on the right tram," Flood said.
"Hopefully he'll get his opportunity to play some AFL footy in the not-too-distant future.
"I think if he does get the chance he'll come in and do well."
Flood describes Sierakowski as a "foot soldier", a disciplined running half-back or midfielder who can also use his excellent endurance to play a run-with role if required.
"His form over the last two, two-and-a-half years has been really consistent all the way through and he's always improving," Flood said.
"He's really switched on with our gameplan, knows our gamestyle.
"He's a smart lad and he just gets the job done."
Although he grew up in rugby league heartland, Sierakowski comes from a rich Australian football bloodline.
His uncle Brian played 75 games, including the 1966 premiership, with St Kilda from 1964-68.
Brian's son David - Will's cousin - played more than 100 AFL games with St Kilda and then West Coast in the mid-late 1990s and early 2000s.
Will's father was also handy, playing for Geelong at under-age level before a knee injury stalled his VFL aspirations.
And although not by blood, four-time Richmond premiership player Michael Green is also in the family, married to Will's auntie.
Despite all of that, it was cricket that commanded much of Will's attention as a youngster.
"I was pretty relaxed about my footy and probably took other sports just as seriously or more seriously," Sierakowski said.
"I didn't mind not having football, football, football all the time.
"Cricket was probably more important to me for quite a while. I loved it."
But his football talent soon shone through and took over.
Sierakowski received the NSW scholarship from Hawthorn at 16, which he says helped put him on the right track with his fitness and diet.
He then played in the seniors at Sydney club North Shore at 17.
Now, after two consistent seasons with Hawthorn's VFL affiliate Box Hill, a dream that once seemed miles away looks a very real possibility of being realised before this season is out.
"There have been a few chats about it," Sierakowski said when asked about his chances of getting a senior game soon.
"Obviously we've got a bit of an extended injury list at the moment, which doesn't help the team but it helps my case.
"So they've said to be ready, because one or two more injuries and there's going to be a few of us who are going to be in really close contention to play."
Mark Macgugan writes for hawthornfc.com.au and covers Hawthorn news for afl.com.au. Follow him on Twitter: @mmacgugan.
