Aubusson will this week become just the 40th player in the NRL's history to play 300 games, and only the third to bring up the total for the Roosters.

A one-club man since his debut in 2007, Aubusson is widely regarded as one of the true club men of the Tri-colours over the past decade.

But Keary was quick to point out his value goes well beyond that, revealing his own disbelief that Aubusson has never been picked to play for NSW or Australia.

"It's a travesty he has never played for his state or country," Keary said.

"Especially at the peak of his career. He is one of the most consistent players who have played in our game.

"He will be held as one of the greatest to pull the Roosters jersey on and probably finish with the most amount of games.

"He is held in very high regard here."

Keary's comments are even more remarkable when you consider some of the players he has put Aubusson alongside.

The list of Roosters greats includes Dally Messenger, Brad Fittler, Arthur Beetson, Ron Coote and Anthony Minichiello alongside current stars James Tedesco and the recently-retired Cooper Cronk.

But Keary said he knew even before he arrived at the Roosters in 2016 how valuable Aubusson was.

"You get to see it more often when you are here.

"But I reckon if you asked a lot of people who have been in the game a long time at different clubs, they know how important a person like he is.

"I think people know what he does for us and what we get out of him."

Aubusson, typically, tried to shy away from the hype of his 300th game when asked about it on Sunday.

He pointed to the match against St George Illawarra being the traditional Anzac Day clash and Tedesco's 150th as bigger milestones around the game.

But when pressed he listed his try in the 2010 grand final as being among the career highlights to go with his three premierships.

"I think maybe I will look back and be proud of it (reaching 300)," Aubusson said.

"But at the moment it's something I have done my whole career, concentrating on the game this week.

"I have done it 299 other times I have worn the jersey, and it won't change for the 300th."

Australian Associated Press