The Panthers' 1449-day run as premiers will go on the line over the next three weeks, as they attempt to come from seventh to win a fifth straight competition.
But in a sport where history has a weird way of repeating, Canterbury loom as their next challenge at Accor Stadium on Sunday.
When Parramatta won three straight titles in the early 1980s, it was Canterbury that stopped their run in the 1984 grand final.
When the great St George team won 11 premierships straight between 1956 and 1966, their dominance was ended when beaten by the Bulldogs in an epic 1967 preliminary final.
And as for who ended Eastern Suburbs' run of three consecutive titles between 1935 and 1937?
It too ended at the hands of Canterbury, with the Bulldogs claiming their first crowne by defeating the Roosters in the 1938 decider.
In fact, since Canterbury's 1935 admission to the NSWRFL, only one run of three straight premierships hasn't been ended by the Dogs.
"Everyone wants to beat the winners," Bulldogs legend Terry Lamb told AAP.
"And that's Penrith right now, with four in a row.
"Everyone wants a challenge … And everyone will remember that stat, who ended it."
A fresh recruit to Canterbury from Western Suburbs in 1984, Lamb said the key to beating an all-conquering team was to break the aura.
"The way I looked at a game was I am a better player than the bloke opposite me," Lamb said.
"Because if you go into a game thinking that bloke is better than me, you're in trouble.
"And Brett Kenny would have done the same against me.
"We became best mates with the Parra guys on Kangaroos tours.
"But as soon as that whistle goes, that mateship is out. It's kill or be killed."
Lamb and his 1984 teammates regularly point to the confidence they took out of beating the Eels a fortnight before the grand final, as well as earlier in the season.
Canterbury sides of 1938 and 1967 also had success over the Roosters and Dragons in the months before their finals bouts.
The Bulldogs enter Sunday's clash in different circumstances, having only beaten a reserve-grade Penrith last month after taking it to the full-strength Panthers in an 8-6 loss in June.
But there is one key element Lamb believes this year's Dogs have on their side.
"You have to remember one thing about Cameron Ciraldo, he came from Penrith," Lamb said.
"He probably knows everything about the players we're playing against.
"You need to play the best game of the year to beat them.
"They will all believe (they are better than their opposite number) on Sunday, no doubt."
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