Viliame Kikau is irreplaceable but Penrith are confident Kurt Capewell is up to the task against South Sydney in Saturday's preliminary final.
The Fijian second-rower was shattered to be rubbed out of the grand final qualifier for an unruly tackle on Jared Waerea-Hargreaves in week one of the finals.
Kikau has been training with the Panthers' second-string side in opposed sessions, giving halfback Nathan Cleary another perspective to the weaponry they will miss on Saturday.
"He's obviously pretty shattered with the news last week but in saying that he didn't let that affect how he was at training," Cleary said on Monday.
"He was running against us in opposed sessions.
"He was up against me and he was bloody hard to tackle.
"I'm glad he's on our team.
"But he's been really good. He just knows he can't change it now."
It opens the door for former Cronulla second-rower Capewell to come onto the edge with double the amount of NRL finals experience.
The 27-year-old played five finals games for Cronulla over four seasons and came off the bench for Penrith against Sydney Roosters in week one.
However, Penrith's injury toll has been so limited this season Capewell has been unable to crack the side consistently, playing just eight games this year.
His last was against Canterbury in round 20 where he scored a double as a stand in for Kikau.
"He's a very hard person to replace, there's not too many that play like him or are built like him but it's pretty handy having someone like Kurt Capewell come in," Cleary said.
"He's played finals before too, we're very lucky in that respect."
Defensively Capewell will need to be switched on against a South Sydney side that has scored 144 points in three games.
It's been a big focus for the Panthers after they leaked 28 points to the Roosters.
"Coming out of that game, defence was definitely the main focus," Cleary said.
"We didn't defend the way we wanted to and we leaked too many points which was uncharacteristic for us."
