UNSW-Eastern Suburbs Bulldogs player Alexander Thompson was on the receiving end of the blow, which reportedly came after an earlier tussle between the pair.
Thompson was knocked unconscious.
Barry Hall's infamous 2008 king hit on Brent Staker will go down as the most brutal in modern AFL footy.
While both were barbaric acts, at least Hall's punch did not come from behind.
The incident is also similar to Reece Conca's Round 19 sucker punch on GWS youngster Devon Smith, who avoided serious injury.
Richmond utility Conca copped a two-week ban from the AFL's match review panel, and is free to play against St Kilda this weekend.
That suspension was widely condemned as too lenient, and there were claims it set a bad example for players in lower leagues.
League boss Gillon McLachlan said it should have been referred directly to the AFL tribunal, which would have allowed more scope for punishment.
Video: Suburban footballer to face hearing over shocking king hit
