Nathan Cleary's readiness for round one is uncertain after being sin-binned in the Panthers' 26-12 trial defeat to Wests Tigers.
He was sent to the bin at Leichhardt Oval after referee Ashley Klein penalised him for a high hit on teenage winger Heamasi Makasini.
The No.7 struck Makasini on the jaw as the youngster juggled the ball in the Tigers' half.
The incident drew jeers from the crowd and has put Cleary's selection against Brisbane in doubt pending a review by the NRL match review committee.
The committee will decide on charges Saturday morning and Cleary's recent history of a careless high tackle in last season's finals only heightens the risk.
If a grade-two charge is laid he could face two matches' suspension even if he takes an early guilty plea, rather than the usual one-game ban.
Jack Cogger, the likely deputy, missed the trial with a niggle, which would further complicate Penrith's preparations if Cleary is unavailable.
Fortunately for Cleary and the Panthers, 18-year-old Makasini walked away from the collision without injury.
Makasini starred for the Tigers, following his hat-trick in Newcastle with a stunning first-half try at Leichhardt.
The teenager produced a 40-metre rampage, shrugging two defenders and powering over Dylan Edwards to ignite the Wayne Pearce Hill.