The 26-year-old former Essendon defender was optimistic on Wednesday morning of adding to the 65 AFL games he played after his 2010 debut.
But the ex-Bomber was not among the 19 players who were rookied after being previously on an AFL list.
Hardingham requested a shift during this year's NAB AFL Trade Period, saying he had been worn down by the Bombers' supplements saga.
He also sought more senior opportunities after struggling for AFL time in the past two years, but was delisted when a deal couldn't be reached.
And the news wasn't good for a handful of other hopefuls who had kept training with AFL clubs.
Former Adelaide forward Jared Petrenko and Gold Coast defender Jeremy Taylor missed out despite training with St Kilda.
Petrenko told AFL.com.au in October that he planned to play for Woodville/West Torrens if he wasn't drafted, and would fight to restart his career at AFL level while playing for his original SANFL club.
Melbourne's big-bodied utility Luke Tapscott wasn't picked up despite being asked to keep training with the Demons after being delisted.
Liam Anthony, who was recruited by North Melbourne with pick No. 43 in the 2008 draft and played 58 games for the Kangaroos, was also left on the shelf.
That was bloody intense sitting and watching a computer screen in hope. another setback to my career but I will be back bigger and better.
— Kylehardingham (@kylehardingham) December 3, 2014
Delisted Bulldogs midfielder Alex Greenwood wasn't given another shot despite continuing to train with the Dogs, while former teammates Mark Austin and Christian Howard also missed out.
Howard will return to SANFL club Glenelg, where he was playing when drafted by the Dogs in 2009 with No. 15 overall in the national draft.
Other former Bombers Cory Dell'Olio and Leroy Jetta, ex-Geelong players George Burbury, Jordan Schroder and Mitch Brown, former Blue Jaryd Cachia, delisted St Kilda defender Sam Dunell and Gold Coast utility Jack Hutchins will also not continue their careers at AFL level in 2015.
Carlton and Melbourne veteran Brock McLean's career appears over after the 28-year-old's name wasn't called out.