Melbourne are promising no let-up as the Storm, Brisbane and Sydney Roosters continue their remarkable domination of the NRL.

At least one of the heavyweight trio have reached 16 of the 20 grand finals since the NRL was established in 1998, with the three-pronged assault to continue as the Storm, Broncos and Roosters vie yet again for spots in this year's title decider.

Only once in 20 years - in 2005 - have none of the three superpowers featured in the preliminary finals, with even Melbourne coach Craig Bellamy left astounded when told of the record on the eve of the Storm's hosting of the Broncos at AAMI Park on Friday night.

The Roosters take on North Queensland on Saturday night chasing their 11th straight victory at Allianz Stadium and a first grand final berth since winning the premiership in 2013.

"That's a pretty good stat for the Roosters, Broncos and Storm," Bellamy said on Thursday.

"It's a nice stat if you're involved in those clubs. I don't know what to say to that; it's pretty astounding.

"It just goes to show the success those clubs have had. I suppose it's good the three of them are there this year."

Melbourne and Brisbane, both one-town giants, and the cashed-up, Bondi-based Roosters have won nine NRL grand finals between them to be dominating like Canterbury, Canberra and Manly did in the 1980s and 90s.

The Bulldogs, Raiders or Sea Eagles featured in 17 of 20 ARL grand finals from 1978 to 1997, gathering 11 titles along the way.

No three sides have dominated in such fashion since St George, South Sydney or Manly featured in 25 straight grand finals from 1949 to 1973 - and winning 23 premierships between them.

Having coached Melbourne to 14 finals series and three grand final triumphs from six title deciders since taking the helm in 2003, Bellamy is already preparing the Storm for life without superstar trio Billy Slater, Cooper Cronk and Cameron Smith.

At 34, Slater remains undecided about his future beyond 2017, Cronk, 33, is moving to Sydney, while Smith will be 35 next year.

"We're certainly going to miss Cooper, we're going to miss Billy and Cameron when they go too. Without a doubt," he said.

"We'll move on. We've got some young players in the club. We're not going to see the likes of those three again, especially playing together at the one club, in the positions they play.

"We'll move and hopefully there will be guys that step up and do a job for us."

In Brodie Croft, the Storm have a Cronk-clone ready to fill the Test half's No.7 jumper next year, with Jahrome Hughes being groomed as a potential fullback replacement for Slater and Brandon Smith said to be ready to take over from Smith.

The Broncos, with prized recruit Jack Bird heading north in 2018, and the Roosters, bolstered by the signing of fellow NSW State of Origin star James Tedesco, also again look to be among the favourites next year.