Brazil's football federation wants sport's highest court to lift a FIFA ban on Neymar playing in two World Cup qualifying matches.
The Court of Arbitration for Sport (CAS) said it aimed to give a fast-track verdict before Brazil played on October 8 in Chile.
Neymar is banned from World Cup qualifiers to complete a four-match sanction imposed in June at the Copa America.
The appeal by the Confederation for Brazilian Football (CBF) challenges FIFA and CONMEBOL rulings that Neymar must serve the ban immediately.
CAS said the CBF wanted the ban applied only at the next Copa America.
A one-off Copa America Centenario tournament could be hosted in the United States next June.
If the CBF appeal fails, Neymar will miss the match in Chile and an October 13 home qualifier against Venezuela.
