In his first audition for the five-eighth jersey since Jarome Luai’s shoulder injury, Cogger threw the last pass for three tries against a dispirited and sloppy North Queensland outfit.
The result settles the make-up of this year’s top eight, with the Sydney Roosters and Canberra both now locked in for the finals.
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For the Rabbitohs, they are feeling numb in what has been dubbed the greatest collapse in NRL history.
Only three-and-a-half months ago they were on top of the ladder, now they are batting off talk of team disunity.
Meanwhile, Newcastle shrugged off the absence of injured talisman Kalyn Ponga and cruised to a 32-12 win over St George Illawarra that also confirmed they will enter the finals as the NRL’s form team – finishing fifth on the ladder.
Sunday’s match between Cronulla and the Raiders is now reduced to a battle for hosting rights of an elimination final in week one, with both certain to make the top eight.
Penrith will face the fourth-placed Warriors in one qualifying final at BlueBet Stadium, while Brisbane will host third-placed Melbourne in the other.
Needing a win to steal the minor premiership off the Broncos and claim the JJ Giltinan Shield for the third time in four years, the Panthers barely looked challenged.
North Queensland spilled the ball twice on the attack in the opening 15 minutes, while Penrith made the most of almost every half opportunity they had in a 26-0 first half.
Most pleasing for the Panthers will be the performance of Cogger.
Star five-eighth Luai returned to training on Saturday and was able to run and pass, but will not play next week
In his place, Cogger was the star of the first half for the Panthers as he had a hand in each of the three first tries.
The 26-year-old put Stephen Crichton over in the fourth minute with a long ball, repeated the dosage for Sunia Turuva 18 minutes later and put Liam Martin through a hole before halftime.
“I thought he was the best player on the field,” Nathan Cleary said.
“Particularly the way he started. He just has a calm head on his shoulder. We combined and communicated well.
“As much as Romi is a loss, Jack has been playing well the whole year when he has filled in. It was no different tonight.”
Rookie hooker Luke Somerton and Cleary also bagged tries, while Brian To’o and Turuva finished with doubles.
The win guarantees Penrith a $200,000 pay cheque to be split between players and club, and preference of changerooms, jerseys and training timeslots at venues through the finals.
Most importantly, the Panthers are now primed for a shot at the league’s first three-peat in 40 years, with a near fully fit squad and hooker Mitch Kenny and second-rower Scott Sorensen set to return next week.
For North Queensland, this was a meek surrender that summed up their season.
After reaching last year’s preliminary final, they spent much of the season chasing their tail after a poor 2-5 start.
And while they clicked through the middle of the year, this was their most disappointing performance since the 48-point defeat to Wests Tigers in May.
Griffin Neame and Zac Laybutt crossed in the first 10 minutes of the second half, but ultimately there was too much to do to save their season.
“It was hard to watch,” coach Todd Payten said.
“With everything to play for and get put on the back foot, not showing any real resolve, was hard to cop.
“Seventeen plays inside our own 20 for five tries, that’s not good enough at NRL level.
“To sit here after 27 weeks, we’re going to watch the finals, probably for more than anything, we didn’t stop enough tries.”
NRL ladder (on Saturday night)
1st: Penrith Panthers (42 pts, +333)
2nd: Brisbane Broncos (42 pts, +214)
3rd: Melbourne Storm (38 pts, +168)
4th: New Zealand Warriors (38 pts, +124)
5th: Newcastle Knights (35 pts, +175)
6th: Cronulla Sharks (32 pts, +104) – to play Raiders, Sunday at 4:05pm
7th: Sydney Roosters (32 pts, -24)
8th: Canberra Raiders (32 pts, -119) – to play Sharks, Sunday at 4:05pm
9th: South Sydney Rabbitohs (30 pts, +59)
10th: Parramatta Eels (30 pts, +13)
11th: North Queensland Cowboys (30 pts, +4) (edited)