Mitchell remains banned from this weekend's decider against Penrith, after copping a six-game suspension for his high shot on Joey Manu in round 24.

The South Sydney fullback could have escaped with a three-game ban for the hit if not for his horror record.

In turn, that would have left him free to play this weekend.

But instead, the 24-year-old's four priors left him facing a ban twice as long, meaning the suspension would have ballooned out to nine matches if he tried to downgrade the charge and lost.

"Should have been making his third NRL GF appearance this weekend but the 'NRL system' had different plans," Mitchell's partner Brielle Mercey posted on Instagram.

"Proud of your efforts this year. You get knocked down over and over and only come back stronger."

It comes after the Rabbitohs pushed for an overhaul of the NRL's judiciary system at the start of the year following another Mitchell charge.

At the time, they wanted a maximum of 25 per cent loading applied for past offences, rather than the 80 per cent Mitchell copped for the Manu hit.

Meanwhile Penrith admitted on Monday they had got too carried away with targeting Mitchell's replacement in their qualifying final loss.

Blake Taaffe will become the most inexperienced grand final player of the NRL era on Sunday night, as he runs out for just his eighth game.

After days of intense build up to their week-one finals clash, Taaffe spilled Nathan Cleary's first bomb but recovered to help the Rabbitohs to a 16-10 win.

"That was probably one thing that happened the first week," Cleary admitted.

"Blake had that early drop and I probably went after him a bit too much rather than going after the field position battle.

"I think it's different each game you get in and the flow of the game.

"We obviously have a bit of a kicking plan going into the game but it changes a bit as the game goes and it's just something you have to adapt to."

Australian Associated Press