Sheffield United have been granted a temporary injunction stopping West Ham appealing to the Court of Arbitration for Sport over the Carlos Tevez saga.
An independent tribunal ruled that Tevez was not eligible to play for West Ham at the end of the 2006-2007 season.
The Hammers want CAS to hear an appeal but Sheffield United claim the court does not have jurisdiction to do so.
West Ham have requested an appeal against the injunction, while United will seek a permanent order next year.
Tevez, 24, who now plays for Manchester United, was deemed by September's independent tribunal to have played a key part in the London's club's Premier
League survival as the Blades were relegated in the 2006-2007 campaign.
"On the totality of the evidence, we have no doubt that West Ham would have secured at least three fewer points over the 2006/7 season if Carlos Tevez had not been playing for the club," the judgement read.
The decision could leave the Hammers liable for damages of £30m.
The two clubs are also set to be involved in a separate directions hearing, in which guidelines for the awarding of damages to Sheffield United will be laid out.
This will involve representatives of the two clubs as well as the three-man panel that sat on the original tribunal in September.
West Ham have already appealed to CAS but, even if Sheffield United's injunction is lifted next year, the Swiss court is not guaranteed to hear an appeal.
The Lausanne-based court is deciding whether or not it would have jurisdiction to hear an appeal and is expected to make an announcement later this month.
BBC Sports News
An independent tribunal ruled that Tevez was not eligible to play for West Ham at the end of the 2006-2007 season.
The Hammers want CAS to hear an appeal but Sheffield United claim the court does not have jurisdiction to do so.
West Ham have requested an appeal against the injunction, while United will seek a permanent order next year.
Tevez, 24, who now plays for Manchester United, was deemed by September's independent tribunal to have played a key part in the London's club's Premier
League survival as the Blades were relegated in the 2006-2007 campaign.
"On the totality of the evidence, we have no doubt that West Ham would have secured at least three fewer points over the 2006/7 season if Carlos Tevez had not been playing for the club," the judgement read.
The decision could leave the Hammers liable for damages of £30m.
The two clubs are also set to be involved in a separate directions hearing, in which guidelines for the awarding of damages to Sheffield United will be laid out.
This will involve representatives of the two clubs as well as the three-man panel that sat on the original tribunal in September.
West Ham have already appealed to CAS but, even if Sheffield United's injunction is lifted next year, the Swiss court is not guaranteed to hear an appeal.
The Lausanne-based court is deciding whether or not it would have jurisdiction to hear an appeal and is expected to make an announcement later this month.
BBC Sports News
