Ivan Cleary knows it. Craig McRae does too.
The NRL and AFL coaches know they didn't just win premierships.
They know their Penrith and Collingwood teams won grand finals instantly bookmarked as all-time classics.
Millions of Australians know it too after the best one-two grand final punches delivered in the same year by the codes.
"The best thing about last night was that that grand final will go down in history," Cleary said on Monday as his Panthers continued celebrating a remarkable NRL premiership.
"No one will ever forget it."
Cleary's Penrith climbed from the proverbial canvas - 16 points down, 18 minutes left - to surge to a 26-24 victory.
The Panthers' third consecutive title came before 81,947 spectators at Accor Stadium.
It came a day after McRae's Magpies captured the AFL premiership through a nerve-jangling four-point win in a see-sawing encounter against the Brisbane Lions.
The margin was never greater than 13 points in a grand final played before 100,024 fans at the MCG.
"On reflection, it was one of the best games I've ever been involved with," McRae said.
Penrith and Collingwood prevailed over Brisbane clubs, the Broncos in the NRL and the Lions in the AFL.
Both were beaten not bowed; winners without winning.
Broncos coach Kevin Walters: "Sometimes the football gods just take things away from you".
Lions coach Chris Fagan: "There's lots of teams in the history of the game that have lost close grand finals that have gone on to win premierships in the ensuing years."
Those philosophical musings followed grand finals which entranced millions of Australians.
The AFL grand final was watched by 4.98 million people on free-to-air Seven Network, plus another 756,000 streaming on 7plus.
The NRL show-stopper attracted 2.9 million viewers on free-to-air Nine Network and another 605,000 via streaming.
Viewers watched unexpected heroes emerge.
Collingwood's Bobby Hill, born in WA's wheatbelt, was a four-goal best-afield Norm Smith medallist; the Broncos' Ezra Mam - who is of Torres Strait Islands heritage - scored a stunning second-half hat-trick of tries.
"It didn't mean much because we didn't get the win," Mam said. "We just couldn't get the fairytale end.
"We got a bit too complacent. You can't really do that against players like Nathan Cleary."
Cleary, son of coach Ivan, set up two tries and scored another himself as the Panthers surged into folklore with the biggest comeback to win an NRL grand final.
"It's the hardest game I've ever played," Nathan Cleary said.
In Melbourne, McRae's captain Darcy Moore received the AFL premiership cup from his father Peter, a former Pies captain who played in five grand finals for four defeats and a draw.
"So many people were heartbroken by all those lost grand finals in his era," Darcy Moore said.
"So to be able to get one back ... and Dad to close the book on that chapter, pass me the cup - wow, I will never forget it."
