The transfer ban handed down to Barca makes it difficult for them to loan the defender back to the Brazilian side for a year and the move is now in danger of falling through
The right-back has long been linked to a move to the Catalan giants, with Sao Paulo confirming on Wednesday that a move is imminent.
However, the deal may be set to collaps as the Brazilian club wish to see the 24-year-old loaned back to them for a season, but with the combination of the transfer ban handed down to the Spanish side by Fifa and the Brazilian transfer window being closed, things have become difficult.
The player must be registered at Barcelona before being loaned back to Sao Paulo, with the alternative being that Douglas wouldn't be able to make the move to Camp Nou until 2016.
Douglas has now returned to training with Sao Paulo and could end up staying there, coach Mauricy Ramalho has warned.
"First we need to get that situation sorted. I can't answer that question and then tomorrow we decide that Douglas will stay," he told reporters.
"We need to sort things out before we start talking. Otherwise we will just create a huge doubt in the player's head.
"Douglas is a Sao Paulo player. If he's in the right condition to play, he'll play. If he has a chance to, he'll play.
"There's no such as thing as holding back. He's ours, not Barcelona's. As long as there's no confirmation that he's out, he'll play. He hasn't signed anything yet."
Ramalho's words, though, are the opposite to those of vice-president Gil Guerreiro, who had earlier ensured the player will join Luis Enrique's side.
"We have everything resolved with Douglas, but no contracts have been signed yet," Gil Guerreiro told Radio Globo.
"There is a small problem now that we're trying to solve. We asked Barcelona to loan Douglas back to us for one year.
"But with their Fifa sanction, they can't. Now our lawyers are studying the situation to see what can be done. But the deal is done, Douglas will be a Barcelona player."