Werder Bremen playmaker Diego has joined up with the Brazil Olympic squad without permission from his club.
The Bundesliga outfit had blocked the 23-year-old from going to the Beijing games, saying he was required for league and cup duties.
Diego appeared to have reluctantly bowed to the wishes of his club, claiming that he was completely focused on the upcoming domestic season.
However, after holding discussions with Bremen bosses on Tuesday he skipped training to link up with his international team-mates in Paris.
Werder are understandably disappointed by the player's actions and are preparing to take the matter to a sporting tribunal in an effort to prevent a vital member of their squad from being unavailable at the start of the new campaign.
"It's better for all parties to clear up the situation," said the club's sporting director Klaus Allofs.
Last season's runners-up in the German top flight have also refused permission for Serbian international Dusko Tosic to take part in the tournament, while their Bundesliga rivals Schalke are facing similar problems preventing Rafinha from taking his place in the Brazilian squad.
The defender set the precedent for Diego when he headed to Paris earlier in the week despite being told not to do so by his club.
As a result, Schalke are now considering legal action against the 22-year-old for breach of contract.
The club's sporting director Andreas Muller was quoted as saying that he would ask the Court of Arbitration for Sport (CAS) to intervene should Rafinha not return to Germany before the competition gets underway.
"He has breached his contract at Schalke," Mueller said, adding the club had sent letters to the Brazilian football association (CBF) and the International Olympic Committee demanding that the player not be allowed to compete.
"If the CBF does not respect our wish, we'll file legal action at the CAS."
Mueller is said to be prepared to fine Rafinha 25,000 euros for every day he is absent, although he would refrain from doing so should the youngster return by the end of the week.
"We hope that he changes his mind," he said.
"There won't be any further consequences for him if he returns by Wednesday or Thursday. I can understand that a young lad wants to go to the Olympics. But the club's interests take precedent."