Super League clubs cannot compete with their NRL counterparts because of the difference in salary caps between the two leagues, according to a leading player agent.
English clubs lost all three matches in this year's World Club Series, with an aggregate score of 118-28 in favour of the Australian sides - the second consecutive season in which Super League teams have suffered a whitewash.
Clubs in Super League are restricted to a £1.85m annual salary cap, a figure which has only slightly risen since its introduction in 1999, while NRL teams are allowed to spend £3.8m each year.
Player agent and former owner of Doncaster, Craig Harrision, says the NRL's dominance of the World Club Series is likely to continue.
"I'd say 99 per cent of it is down to the salary cap, plus the weather," Harrison said. "I watched some skill sessions earlier in the year and they had to be stopped because of the weather.
"At the time it was 90 degrees in Australia. The facilities over there are ridiculous compared to what our lads have to deal with. Only Warrington have an indoor skills facility."
A number of England internationals, including Tom Burgess, Josh Hodgson and Gareth Widdop, have moved from Super League to the NRL in recent years, attracted by the higher wages on offer.
Harrison believes that more English-based players will follow unless Super League officials address the imbalance.
"It won't be a lot but it will be the elite, the X-factor players like Ben Currie and Zak Hardaker," he added.
"They will have to go eventually because it's impossible to keep a player on £130,000 or £140,000 a year when he can earn £600,000 or £700,000 in Australia.
"And we can't attract the calibre of player like Ali Lauitiiti and Brent Webb any more, there's no chance of bringing a Kevin Iro over here.
"When we were strong, when Wigan and Ellery (Hanley) ruled the world, they had Dean Bell and other top-quality international players boosting that squad."
Harrison believes that the gap between the two leagues is now so big that the World Club Series should instead pit the NRL's worst sides against England's best.
"My suggestion would be to play the bottom four of the NRL, that would be more of a leveller," he said.
"We shouldn't expose ourselves until we've got enough quality. If we play their bottom four, we know where we are then. That would be a good marker."