A video emerged on Wednesday morning of Treloar wearing a Collingwood polo, signing a contract and talking about his excitement in moving to the Lexus Centre.
It is an embarassing leak for Collingwood, who have suggested that a 'hacker' was responsible for the content being revealed online.
The vision, that was apparently filmed last Friday, shows the 22-year-old talking extensively about "joining" Collingwood.
"It's been a tough decision, but one that I am at peace with. I think it is the best decision for myself and my family, and I can't wait to get stuck into the pre-season and run out in round one in front of hopefully 90,000 people," Treloar said in the video.
"At the end of the day I always wanted to come back and play in Victoria around my friends and family. I can see them whenever I want. I've got a young sister and young brother who I'm super close with.
"We narrowed it down to two clubs and Collingwood was the one I chose obviously."
Watch the video here.