BBC | Barcelona have lost another appeal to register Spain forward Dani Olmo for the rest of the season - one day before the deadline.
The 26-year-old was was signed from German side RB Leipzig for a reported 60m euros (£51m) in August.
However, he was registered only for the first half of the season as Barcelona could not meet La Liga's wage cap restrictions.
A court rejected Barcelona's attempt to re-register Olmo last week, with a second court backing the decision on Monday, meaning he may not be able to play for the club from 1 January.
According to La Liga, the court rejected the precautionary registration of Olmo after "none of the conditions necessary for the adoption of the precautionary measure were met".
La Liga also defended the competence of its Delegate Commission to approve its budgeting rules, adding "this has never been questioned by any club, including Barcelona".
The Spanish league said the decision not to register Olmo, who was a youth player at Barcelona but left for Dinamo Zagreb aged 16, was initially taken by its Budget Validation Body.
It was then confirmed three times by its Financial Fair Play Committee, its Social Appeals Committee and by the Uefa Second Instance Licensing Committee of the Spanish Football Federation.
Barcelona decided on the judicial route, but now face a race against time to find an alternative plan to register Olmo or he could become a free agent, with Premier League clubs reportedly interested.
Spanish media reports say the club is planning to sell VIP boxes at its Camp Nou stadium which could bring in over 100 million euros, but it will need the approval of La Liga.
Olmo, who helped Spain win the European Championship in the summer, has scored six goals in 15 appearances for Barcelona this season.
Hansi Flick's side are third in La Liga, three points behind leaders Atletico Madrid.
