FC Sion have lost their fight to be allowed back into the Europa League.
The Court of Arbitration for Sport upheld Uefa's decision to expel the Swiss club from of the competition for fielding ineligible players.
Five such players were fielded in Sion's two-legged play-off win against with Celtic, who were reinstated in the competition after making a complaint.
Sion have also been ordered to pay Uefa 40,000 Swiss Francs for the governing body's legal costs.
However, the Swiss club intend to challenge the verdict and have 30 days to respond officially.
A CAS statement read: "The CAS first decided that it had jurisdiction to rule on the request for arbitration filed by Uefa on 26 September 2011.
"It then decided to confirm that OLA (Sion) should not be reintegrated in the UEFA Europa League 2011/2012, confirming indirectly the validity of the decision of the Uefa Appeals Body of 13 September 2011."
Two courts had ruled Sion could register six players despite a Uefa transfer ban, and should have been reinstated.
Sion took the matter to CAS after world governing body Fifa appealed successfully to the higher court.
The outcome of the ruling could have had implications on Europa League Group I, which features Celtic, Rennes, Udinese and Atletico Madrid.
The six players in question joined Sion in the close season when the club was serving a ban - lasting two transfer windows - for breaching rules in the signing of Egyptian goalkeeper Essam El Hadary in 2008.
The players won the right to play in August after taking their case to a court in Martigny, Switzerland, and the club won an injunction ordering their reinstatement at a further hearing at one of the country's civil courts, this time in Vaud.
As a result, the Swiss Football League (SFL) backed down from enforcing the Fifa ban in domestic competitions.
But Fifa announced in a statement that their appeal against the Martigny ruling had been successful.
Uefa insisted that CAS was the only valid authority with jurisdiction over the matter, after Sion claimed Uefa denied the club access to an "independent and impartial judge" and breached the players' working rights under the European Union-Swiss treaty.
In response to the CAS ruling, a Sion spokesman said: "The verdict makes stronger our feeling of the servility of the CAS to the powerful football authorities. It confirms our belief that now it becomes urgent to change the functioning of that court, which ultimately is not one.
"We are now taking the case in front of Swiss Federal Court (the CAS recognises its authority), and then the European Court."
Sion were helped in their case against Uefa by Jean-Louis Dupont, the lawyer who won the landmark Jean-Marc Bosman ruling in 1995.