Leeds have won the first battle in their bid to claim compensation for the failure of their former captain Iestyn Harris to return to the club.
A judge ruled that Leeds had first refusal on Harris' services
A High Court judge ruled that Leeds had first option if the player returned to league from union and ordered Bradford to pay Leeds £64,000 in legal costs.
Harris joined Bradford on a three-and-a half year deal when he came back to league instead of rejoining Leeds.
A full trial will now be held to determine liability.
Leeds alleged that Bradford had enticed Harris, who played for Wales in the 2003 union World Cup, to breach the agreement.
The judge, Justice Gray, added that, although the clause in Harris' release agreement did amount to a restraint of trade, it was a "reasonable" one in all thecircumstances and the player was "more than willing" to sign it in order to achieve his dream of playing for Wales.
"It was entirely reasonable for Leeds to reserve the right to call upon their former star player to play again for the Rhinos," he said.
Leeds chief executive Gary Hetherington, who attended the hearing in London, said: "We are naturally pleased that Mr Justice Gray has upheld the validity of the contract between Leeds Rhinos and Iestyn Harris and legal proceedings will continue."
A Bradford spokesman said: "We have received the decision handed down in the High Court and, with our legal representatives, are looking at the implications of the decision. We will not be commenting further."
Harris said he was "disappointed" by the verdict.