James Maloney will have scans on his injured foot but will miss Penrith's NRL clash with Cronulla alongside Nathan Cleary and Tyrone Peachey after coach Anthony Griffin confirmed they'd be rested.
Maloney went over on his foot during the second half of NSW's State of Origin III loss to Queensland on Wednesday night, but he played on after limping briefly and only reported it as being sore after the match.
Both Cleary and Peachey have been given a clean bill of health by the club's medical staff, but also won't feature in the crucial clash for the top four.
In their place Jarome Luai and Tyrone May will stay in the halves, after the young pairing trounced the Warriors 36-4 in their first game together last week
"Jimmy has got a little thing we want to get checked out, a sprain on his foot," Griffin said on Thursday.
"We will rest those guys and go without them tomorrow.
"They were always going to have to have a rest at some stage.
"It certainly helps with the confidence of guys who are playing tomorrow night with the long-term view to the back end of the season we were always going to rest them at some stage."
Penrith's win last weekend was their biggest of the season but they acknowledge the Sharks will be a different beast.
Only Valentine Holmes is backing up from Origin at Panthers Stadium and he was named by Cronulla earlier this week.
It also shapes as a crucial one in the battle for the top four, with Penrith currently fourth but with a tougher run home than those above them and immediately below them.
A Sharks win would also see Cronulla join the Panthers on 24 points, however with a far poorer for-and-against.
"Tomorrow is another big test," Griffin said.
"The Sharks are a lot older and experienced group than what the Warriors were and they play a different style of football. We prepared pretty well for that.
"Our club has done a terrific job all year against some adversity with injuries.
"We've had a lot of our salary cap on the sideline for long periods of time. Key positions as well. Without looking at the ladder it's just another good opportunity for us to put in a good performance as a club."
Griffin also said he wasn't fazed by Cronulla bench hooker James Segeyaro's comments earlier this week that he and Matt Moylan find it easier to get up for games against Panthers after the terms on which they left the club.
STATS THAT MATTER
* Cronulla have won their past four and nine of their last 11 against Penrith.
* Cronulla are chasing their 300th try against Penrith - their 299 is the most they have against any club.
* Penrith have scored the second-most second-half points this year (208), and conceded the second fewest (102).
Stats: Fox Sports Stats