Cleary stole the show in Saturday's preliminary final at Accor Stadium, setting up three of Penrith's four tries, kicking a pivotal 40/20 and converting four goals from five attempts.
But the halfback's fitness is expected to come under the microscope ahead of next Sunday's meeting with the Melbourne Storm after he reeled out of a tackle late in the preliminary final.
Cleary got through more defensive work after the collision but was taken off as a precaution with five minutes to go.
Nathan Cleary leaves the field with a shoulder complaint, but with a win in the bag. (Dan Himbrechts/AAP PHOTOS)
The only other concern for the Panthers will be the availability of hooker Mitch Kenny, who was placed on report for a high shot that took out Sharks prop Tom Hazleton midway through the second half.
Cronulla were gallant throughout the game but they struggled to ice the chances that fell to them.
Penrith, by contrast, had no such issues.
Their pursuit of a fourth consecutive premiership and a passage into a fifth-straight grand final was not without its challenges but they showed the maturity and ruthlessness that has them on the cusp of more NRL records.
The Panthers hit the lead when Toby Rudolf was penalised for a trip on Isaah Yeo after six minutes and Cleary kicked a penalty.
Nicho Hynes soon tied things up from the tee and the Sharks proved a match for the Panthers up the middle.
But in the space of 90 seconds Craig Fitzgibbon's side got a glimpse into why Penrith call themselves three-time reigning premiers.
After a knock-on denied Hynes a try that would have put the Sharks in the lead, Cleary relieved some pressure by booting a 40/20 on the next set.
Suddenly entrenched in Cronulla territory, the Panthers wasted little time as Cleary sent an inch-perfect ball for centre Paul Alamoti to crash over.
Paul Alamoti charges through for one of Penrith's four tries. (Dan Himbrechts/AAP PHOTOS)
Cleary converted his try and added a penalty - Sisosifa Talakai was penalised for a late hit on Jarome Luai - to give the Panthers a 10-2 halftime lead.
Both sides were wasteful in possession through the opening 20 minutes of a tense second half but when Kenny hit Hazleton high, Cronulla found the breakthrough with a sweeping play to the right.
Sione Katoa touched down in the corner to cut Penrith's lead to just four points but Hynes was unable to convert from the sideline to reduce the deficit further.
In the mood for more, Sharks prop Oregon Kaufusi made a handling error and Penrith smelt blood.
Cleary put Brian To'o over with a crossfield kick, before setting up Alamoti for his second try of the night before being taken off, with Liam Martin rounding out the rout.
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