AS MICK Malthouse gets back into the groove of weekly pre-match news conferences, he hasn't taken long to get back to holding the AFL accountable.

The Carlton coach has taken a swipe a several of the League's NAB Cup trial rules, including the out-of-bounds rule and interchange cap.

"Last touch over the line is ridiculous, cause it just murders players, they can't go a yard in the last quarter," Malthouse said on Wednesday.  

"When you have total fatigue you have breakdowns."

"If we're going to have the 80 (interchange) rule, please let us coach. So if I want to use 50 in the first quarter and 10 in the last, let me coach the side."

Malthouse said if the League hadn't allowed an extra two substitutes for rounds two and three of the NAB Cup he wouldn't have been able to play some of his players, some of who are only ready for a quarter or half of football.   

He's also worried about the long-term impact of an interchange cap, if the League goes down such a path permanently.

"I think players who are six minute players who just get on, and burst, and really give us something to look at, they're now going to be eight or nine (minute) players," Malthouse said.

"That player will play because he's good enough, but he won't be playing the same dynamic type of game."

"We're changing everything really, which is a little bit of a shame in many respects."

But there is one change Malthouse would endorse, a potential measure to eradicate the dangerous sliding tactic from the code.

"I'd change it so when you're on the ground you should not be allowed to (pick up the football.)

"You can tap it out, knock it out, kick it out, but you can't pick it up."

The Blues meet Fremantle in the NAB Cup Saturday night, presenting another chance for Mathouse's charges to perfect the new game style he's introduced, a process that's taking its time.  

"Unfortunately patience is for the dead, so it doesn't really suit me, but I'll have to live with it," Malthouse joked.  

Matt Thompson is a reporter for AFL Media. Follow him on Twitter @MattThompsonAFL