The Hoops are closing in on a deal for the 32-year-old after the Brazil international made the trip to Loftus Road on Tuesday to agree personal terms.
Hughes has already brought in England goalkeeper Rob Green on a free transfer this summer, and the QPR boss is delighted to add another top shot-stopper to his squad before the window closes next Friday.
“There’s nothing concluded yet,” Hughes said. “There are a number of papers that need to go back.
“We’re not at a point where we can actually say it’s a done deal.
“The intention is there obviously if we can but at the moment it’s not concluded.
“I said I wanted to have two quality keepers this window if at all possible. Sometimes when opportunities present itself you want to pursue them.
“When you get an opportunity to possibly bring a player of the quality Julio Cesar’s quality, with his playing record and his mentality, then I think you have to pursue to its conclusion.
“I think when we started the process we probably never thought there was an opportunity or chance he would be able to come here. If we are able to conclude it, we’ll be delighted.”
Hughes also revealed Joey Barton’s move to Marseille may still be on despite the midfielder claiming on Twitter that a proposed loan switch to the Ligue 1 outfit had been called off.
“The Marseille ordeal may not be dead in the water,” he added.
“We might be able to get a solution for everybody. This option has attracted Joey’s enthusiasm so hopefully it is concluded.”
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