Super League champions Leeds have been refused permission to loan veteran Samoan prop Kylie Leuluai to neighbours Hunslet.
The Rhinos have a partnership with the Hawks in which players not required for Super League duty can be dual-registered to turn out for the Championship club.
Leeds wanted Leuluai and fellow front rower Richard Moore to gain match practice with Hunslet against Leigh on Sunday after not figuring in their opening match of the season against Hull last Friday.
However, the Rugby Football League say they have been told by the UK Border Agency that, under the terms of his visa, Leuluai is unable to become a dual-registered player.
The ruling, which only affects overseas players, will have repercussions throughout the game.
It follows the cost-cutting decision to scrap the Super League clubs' Under-20s competition which was used to keep fringe players active and ease others back into action from injury.
Bradford were hoping to allow Australian centre Adrian Purtell to make his comeback from a heart attack with their partnership club Dewsbury but will now be forced to throw him straight back into Super League when he completes his recovery.
A League spokesman said: "The RFL has recently lobbied the UKBA for a change to the rules which prevent players on tier-two visas playing for a second club on a short-term arrangement.
"This follows on from changes to the Super League Academy structure, which from 2013 is an exclusively Under-19s competition, an arrangement that means open-age overseas tier-two visa players returning from injury cannot gain match fitness on short-term loans or dual registrations.
"Dialogue with the UKBA continues but the UKBA have confirmed that, until any change in circumstance is agreed, under existing provisions no player on a tier two visa can be dual registered."
Leeds reacted with disappointment to the ruling, with chief executive Gary Hetherington criticising the role of the RFL.
"This decision is purely down to bureaucracy and red tape and it is so disappointing that rugby league players are treated differently to other professional sportsmen and how little influence our governing body seem to have compared to other sports," Hetherington said.
However, the ruling was welcomed by Halifax, one of three Championship teams who have refused to enter into partnerships with Super League clubs.
Halifax claim the dual-registration system is turning the lover-division teams into "feeder clubs" and argue the Leuluai case demonstrates "the short-sighted and foolish nature" of the decision to scrap the reserve grade in Super League.
Halifax chairman Michael Steele said: "There can be no justification for the use of the Kingstone Press Championship as a venue for securing the fitness of established Super League players.
"The sooner the Super League clubs and RFL recognise the mistake they have made and rectify it without taking the Championship for granted, the better the prospects for the future of the sport."
Friday's ruling has added fuel to the debate over the relationships between Super League clubs and those from the Championship but in the meantime St Helens' former England winger Ade Gardner will play on a dual registration for Whitehaven at Keighley on Sunday.
Warrington prop Paul Wood, who was a member of the the Wolves' Grand Final team in October, began the season playing for Swinton against Workington last Sunday.
what do you think?
Good! Because it doesent realy seem very fair to me that these clubs in league 1 and 2 are getting stars like this.