FIFA may allow Romario to play for Vasco despite a regulation that would keep the striker out until June.
Soccer's governing body prohibits players from playing for more than two clubs in a 12-month period, and Romario has already played for Miami FC in the United States and Adelaide United in Australia.
FIFA last week sent a letter to the Brazilian Soccer Confederation, however, asking if it had any objections to letting Romario play in a signal that he might be cleared to join Vasco before June.
"We said there are no objections," CBF lawyer Valed Perry told today's edition of Lance. "FIFA came to us, so it appears to be inclined to let him play."
Vasco lawyer Marcos Motta said FIFA may be willing to bypass its own regulations because the Brazilian soccer calendar is different from most of the world.
"Romario would not be signing with a club in the middle of a competition," said Motta, noting that the Brazilian league is yet to start.
Still, Motta said Vasco will wait for a final decision from FIFA before signing the 40-year-old Romario, who has been practicing at the club since the beginning of the year.
The striker says he is 13 goals from reaching the 1,000th career goal, a feat achieved only by Pele. Romario, who led Brazil to its fourth World Cup title in 1994, signed briefly with Brazilian club Tupi FC last year, but also wasn't allowed to play.
The deal was seen mainly as a marketing move. In his prime, Romario played for FC Barcelona, Valencia and PSV Eindhoven. Vasco, where Romario began his career, is currently playing in the Rio de Janeiro state championship.