Weideman was born into an Australian rules football family with his grandfather, Murray Weideman, playing 180 matches for the Collingwood Football Club, including winning two premierships (he captained the 1958 premiership), winning three Copeland Trophies as Collingwood's best and fairest, and is a member of the Australian Football Hall of Fame; his father, Mark Weideman, also played for Collingwood, playing 28 games.

[1] Although both his father and grandfather played for Collingwood, he grew up a passionate supporter of the Richmond Football Club.

[11] As part of the AFL Academy, he played two matches in April against Victorian Football League (VFL) sides, Werribee and the Northern Blues, both at the Melbourne Cricket Ground,[12][13] in the second match, his first quarter saw him kick two goals and take five marks and he was named in the best players by AFL Media.

[16][17] After playing no football since May, doubts surrounded Weideman and his injuries,[18][19] however Eastern Ranges talent manager, Len Villani, noted "his qualities made him a rare commodity",[20] and the AFL Academy coach, Brad Johnson, stated "every now and then you’ll see things from him and you know with good development into the future, he’s going to turn into a really strong, consistent performer"[21] and "the right people have seen enough already through his junior days to say he’ll be able to get back to some pretty strong fitness, work on his endurance and become a really good hit-up forward".

[33][34] The match against Coburg was labelled his best for the year by Casey coach, Justin Plapp,[35] and after kicking twenty goals from eleven matches,[36] he made his AFL debut the next week in the twenty-nine point win against the Hawthorn Football Club at the Melbourne Cricket Ground in round 20.