Football's ruling body FIFA said on Sunday that a Spanish appeal against an extension of the international window for World Cup qualifiers in South America has been rejected.
FIFA said the Court of Arbitration for Sport (CAS) confirmed its decision to add two days to the September window.
Spin's La Liga went to CAS claiming FIFA was violating its own statutes when it added the additional days in order to stage additional qualifiers cancelled earlier in the year owing to the coronavirus pandemic.
"Today's CAS decision confirms the legality of FIFA's decision and entirely rejects the arguments made by Spain's La Liga," FIFA said.
"We now expect the release of players for the upcoming FIFA World Cup qualifiers in South America to occur in accordance with the recent FIFA decision."
FIFA President Gianni Infantino had earlier in thr week called for a show of solidarity from all member associations.
Spain didn't want to release dozens of players because the extended window September 2-10 would impact their next round September 11-12.
England's Premier League also said its clubs would not allow nearly 60 players to be released for international matches played in red-list countries which would require a 10-day quarantine period in a hotel on their return.
