Frustrated Carlton coach Michael Voss has hit out at the AFL over the "crazy" need to omit a player from the team's 22 to be included as the substitute.

Voss has confirmed Matt Kennedy will be the Blues' sub against West Coast on Saturday night, less than 24 hours after the midfielder was listed as omitted.

Kennedy's perceived axing following a disappointing loss against St Kilda came as a shock to some Carlton supporters, but Voss clarified the 26-year-old would play a role against the Eagles.

The former Brisbane Lions champion said clubs were required to omit a player from the 22 when naming their teams ahead of a round if they wanted to be the sub.

"Matty will be sub so I don't mind disclosing that," Voss said at Optus Stadium on Friday.

"That's just the nature of the way we select the teams now.

"It's just really one of the craziest rules I've ever seen, the fact you have to omit someone to put someone back in I just don't know why he can't be named the 23 but it is what it is."

Voss remains confused by the system, and he is not the only one.

Richmond coach Damien Hardwick was livid about "omitting" Trent Cotchin for the Tigers' round four clash with the Western Bulldogs even though the three-time premiership captain was always going to be the sub.

"I think it's ridiculous that we've got to do it and we need to get it fixed. It's farcical that we've got to do it," Hardwick said after the defeat at the MCG.

"It'd be nice if the AFL could do something about that so it doesn't create a big story."

Voss said he and the Blues had put in a "submission" and sought out an explanation from the AFL, but they continue to be perplexed.

"What we're told is that there's a few laws that need to be rewritten - that's at least what we've been told," Voss said.

"Hopefully by the time we get to the end of the year, they look at it pretty closely and actually spend a bit of time rewriting the rules because it needs to change."

The AFL has been approached for comment.