The club even threatened to go as far as the Court of Arbitration for Sport (CAS) in an attempt to stop Rafinha.

"We have written to the Brazilian Football Federation CBF and the IOC (International Olympic Committee) demanding that Rafinha be prevented from playing at the Olympics," said Schalke general manager Andreas Mueller.

"If the CBF doesn't comply with our wishes then we will take the case to CAS," he added.

Earlier on Monday, the Schalke defender left his club's training camp in Austria in order to join the Brazil Olympic squad despite being refused permission to travel.

Rafinha, Diego of Werder Bremen and Bayern Munich's Breno have all been selected for Brazil's Beijing Olympic squad but Breno is the only one to have received permission from his club to travel to China.