His comments come after Collingwood defender Ben Reid was penalised for shoving Essendon's Tom Bellchambers in the side during a marking contest on Anzac Day.
AFL umpires chief Jeff Gieschen has since declared the decision was correct, as players were not permitted to "push, bump, block or hold in a marking or ruck contest".
Gieschen told AFL.com.au not only a push in the back should be be penalised.
"You can't push in the side, you can't push in the chest, you can't push in any part of their body in a marking contest," he said on Monday.
His comments have concerned Rockliff, who told SEN Radio on Tuesday he was unaware of the rule.
"That's the first time I've ever heard that, and honestly I'm not one to make stuff up or lie," he said.
"That's the most bizarre thing I've ever heard."
Rockliff thought the Reid penalty was incorrect at the time.
"I thought that was just a show of strength.
"He stood tall in the contest, took the mark, and if you take that away from our game it's going to become a very soft game, and unfortunately that's not going to be the best thing for the AFL.
"If you take away a show of strength, I'm not sure what they expect, how you're supposed to win a contest.
"Otherwise we'll just have 22 athletes running around there, and we might as well not be playing with an AFL footy, and make it non-contact."
The midfielder also believed the new contact below the knees rule needed tinkering.
"I think the rule does warrant it, and you don't want to see blokes slide in and taking blokes legs out, because you do get the serious injuries, but there's got to be commonsense," Rockliff said.
"That's probably the hardest thing for the umpires at the moment, and I do feel sorry for them that they've been told to pay free kicks for the sliding intention, but it's got to be the force on them.
"If someone's leading with their heads first to win the footy and they've got their heads over it and they make contact with someone's legs, then commonsense has got to prevail.
"I think the ones we've got to get out of the game are where they're running from 20m and they're sliding nearly legs first or going to take someone's legs out. They're the really dangerous ones."
His comments have garnered support from Richmond defender Steven Morris, who tweeted, " I think players & fans would agree with a lot of what was said".