Panthers halfback Nathan Cleary passed a SCAT test after a high shot from Dallin Watene-Zelezniak but remains in some doubt for Thursday night's grand final rematch against Melbourne.
Cleary's departure from the field with 10 minutes remaining put a downer on Penrith's 28-0 shutout performance over the Bulldogs at Bankwest Stadium on Saturday with the halfback set for light duties during the five-day turnaround before the Storm clash.
A dazed Cleary was collected by Watene-Zelezniak's shot as the Panthers halfback defused a kick and raced 40 metres downfield.
Watene-Zelezniak was placed on report for the incident before being sent to the sin-bin in a disappointing afternoon out for Cleary's former Panthers teammate.
Panthers coach Ivan Cleary wouldn't weigh into the tackle from Watene-Zelezniak, declaring "everyone saw what happened", but said his son had shown positive signs post-match.
Match Highlights: Bulldogs v Panthers
"He's good actually, he passed his SCAT test but all signs at the moment is he's pretty good," Cleary said.
"There are protocols to go through so we'll see what comes of it. We've got Matty Burton sitting in the background so maybe it's his week."
With Matt Burton's name a hot topic in the lead-up to the clash as he has signed with Canterbury for 2022, the Panthers may need to call up their back-up playmaker for the grand final rematch.
Burton ready should Cleary be unavailable for Storm battle
Burton wouldn't have been able to turn the result around for the Bulldogs in torrential conditions on Saturday with the Panthers running in five unanswered tries to keep the opposition to nil for a second consecutive week.
Penrith's defensive efforts continued and saw them become the first club in rugby league history to hold teams to nil in the opening two rounds of the season.
Two tries each to Viliame Kikau and Paul Momirovski set up the win as both edges fired against a Bulldogs outfit that fell away in the second half.
"I thought we were really patient and disciplined today so that was always going to help in a game like today," Cleary said.
"I thought we kicked really well and dominated field position and possession. That was the order of the day and I thought we did it well.
"We value [defence] and work really hard at it. Our defensive coach Cameron Ciraldo does a great job. When I first came back to the club in 2019 we changed the system quite a bit and that took a bit of time.
"Under Cameron's tutelage it's developing nicely and the boys have bought into it and it all rolls into one, if we're dominating field position and possession then defence is a lot easier."
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The Panthers lost Api Koroisau pre-game after scans revealed a wrist fracture suffered in last week's win over the Cowboys with Mitch Kenny stepping up in the rake's absence.
Kenny came up with a couple of errors but topped the visitors' tackle count with 45.
Cleary expects Koroisau to miss around six weeks, opening the door for Kenny to make his mark in the team.
"Mitch is working away at his craft but with Api's injury he's going to get significant time to not rush things and show what he's got instead of one game here or there," Cleary said.
"There were a couple he didn't get to in the period where we got a bit scrappy but a nice pass for Kiks to go over the line, which was a key try for us in the second half. His defence was resolute as it always is.
"We look forward to him see him develop over the next 5-6 weeks."