Instead, like so many talented basketballers before him, Downie switched his attention to the AFL, showing enough in his final year of high school and with the North Ballarat Rebels to be drafted in 2011.
Downie played Auskick as a child, but spent his teenage years with a round ball rather than a Sherrin, before a late decision to return to football.
Considered very much a project player, the 203cm ruckman has improved enormously in 2013 and will make his debut against Fremantle on Sunday.
Following an inconsistent first season with the Giants as he adjusted to the professional ranks, Downie knew it was crunch time in 2013, the final year of his contract.
And he has blossomed, regularly named in the reserves' best players over the past month to force his way into the senior team.
"I actually found out in front of the group on Monday," Downie told AFL.com.au on Friday during a visit to the Sydney Children's Hospital as part of the club's 'Gentle Giants' program.
"I'm rapt to be playing my first game for the club.
"Last year I had a few good games, but there were times where I was struggling for form.
"But this year has been a lot better.
"I've been confident in my ability from the start and that's obviously why I made the move.
"I was hoping to get a game this year and it turns out I've been lucky enough to do that."
Some of Downie's former teammates have moved into the professional basketball ranks, including Townsville Crocodiles point guard Mitch Norton and Melbourne Tigers small forward Owen Odigie.
But Downie has no regrets about his career choice and will face a man on Sunday whose size would have also left him well suited to a career on the hardwood.
Aaron Sandilands stands just under seven feet and will be one of the few ruckman in the competition to look down on Downie.
"Obviously any game would've been tough first up, but this is something different," Downie said.
"I think most ruckmen in the AFL find it a challenge coming up against Sandilands."
Mobile for a big man and blessed with good hands, Downie has improved dramatically at stoppages and around the ground this year.
GWS coach Kevin Sheedy has noticed.
“He’s really started to move through the ranks with his performances in the NEAFL and has played very well in the last month in particular," Sheedy told the GWS website.
“He’s a very mobile ruckman who’s getting more confident every time he plays the game and as he continues to develop I think he’ll become a terrific player for the Giants."
Now all that's left is for Downie to conquer the five-hour flight to Perth.
"It's a long flight over there," he said. "Fingers crossed I get an exit row seat."
James Dampney is a reporter for AFL Media. Follow him on Twitter @AFL_JD