Where once the footfalls of a gigantic Green Machine pack could be heard down the Hume highway, Ricky Stuart's Raiders have been trimmed down to become one of the NRL's lightest forward contingents.

Canberra head into 2019 having missed out on the finals for a second year running and farewelled monster props Shannon Boyd (Titans) and Junior Paulo (Eels).

With that pair packing down at a combined 245 kilos, and incoming English internationals Ryan Sutton (103kg) and John Bateman (96kg) making a much smaller dent at the buffet, the Raiders edge and middle rotation will carry roughly 50 kilos less than last year.

Excluding hooker Josh Hodgson (94kg) and expected back-up/utility Siliva Havilii (104kg), Canberra's predicted starting and bench forwards will drop from an average of 109 kilos to 103, ranking them alongside the title-winning Roosters as the 'smallest' big men in the game.

With Victor Radley (92kg) and Mitch Aubusson (96kg) offering mobility over mass, the Tricolours' likely eight-man rotation clocks in at a combined 827 kilos.

At the other end of the scales, figures obtained by NRL.com indicate that the Cowboys with colossuses Jordan McLean (118kg), Jason Taumalolo (117kg), Coen Hess (114kg), Scott Bolton (112kg) and Matt Scott (110kg) shape as the heaviest pack in 2019, closely followed by the Storm, Warriors and Eels.

Canberra had made power and prime beef a key focus in recent years, to the point where all 120-plus kilos of Dave Taylor lined up alongside Boyd, Paulo and Papalii during a 2017 stint in the nation's capital.

But the club's veteran recruitment manager Peter Mulholland says the departures of Boyd and Paulo, while also influenced by big dollars on offer elsewhere, did signal a shift in strategy for the Raiders.

"You look at factors like mobility there, sometimes it's salary cap issues as well, you know what you want to pay for a player that plays 40 minutes," Mulholland told NRL.com.

"You can't have it both so you let them go. We've lost a bit of an X-factor with both of those boys and I don't think you can have two of them at your club.

"Perhaps one but once again we're looking at mobility and what's still a pretty decent pack of forwards.

"You've still got Josh Papalii who will probably start in the front row, we've got a decent sized pack of forwards still without that heavyweight contingent."

Balancing size and stamina is itself a weighty act in the modern game.

See last year's grand finalists and perennial heavyweights the Roosters and Storm occupying different ends of the pack weight spectrum.

Melbourne's combined kilos are blown out by the inclusion of Sam Kasiano – listed at 126kg – on their predicted bench having overcome an injury-plagued first season down south.

Similarly, Havili's added bulk as Canberra's utility allows them to play either he or Hodgson – typically an 80-minute hooker – as a roving middle forward.

Paul Green makes a point of ensuring North Queensland's brawn is delivered with a difference too.

When James Tamou (195cm, 115kg) moved to Penrith two years ago, Green specifically scouted for tall timber to replace him up front, eventually landing on the 196cm, 118kg McLean from Melbourne.

Green's theory is that a variety in height and body type makes more work for opposition defences, who must adjust from tackling Josh McGuire (180cm, 104kg) to Bolton (187cm, 112kg) to McLean in an instant.

Match Highlights: Raiders v Eels

It's horses for courses, but the nature of the beast comes into play as well for Mulholland.

Especially if the NRL continues to chase a faster game with more ball-in-play time, with potential for reducing allotted interchanges discussed each off-season by the competition committee.

"At the moment there's a place still for the big men but it depends on their engine," Mulholland said.

"A guy like Sam Kasiano at the right weight – 118-120 kilos – he can play big minutes, he's got that big an engine. But other guys don't have that aerobic capacity, a lot depends on the animal himself.

"And it's not just about attack either, a lot depends on defence and how they fare with lateral movement when they're fatigued.

"But if the game's going to speed up again there will be another evolution needed for those big men".