The England centre-back has been sidelined since suffering a thigh injury last month and has only featured in the Community Shield so far this season.
However, the 30-year-old's recovery from the injury has been quicker than expected and could feature at the weekend.
"Rio has been in training this week and has a got a chance for Saturday, I'm not sure how big a chance but he has got a chance," said Ferguson.
"We've had a good group of players training here at Carrington while the internationals have been going on - Ferdinand, Paul Scholes, Ryan Giggs, Gary Neville, Anderson, Ji-sung Park as well as young Fabio and Michael Owen.
"So we have a decent squad. In fact, it's unusual to have that many players here [during the international break]."
However, full-back John O'Shea is set to be missing after suffering a calf injury on duty with the Republic of Ireland.
Ireland's coach Giovanni Trapattoni had warned that O'Shea could be ruled out for a couple of months if he is rushed back into action too soon.
Ferguson said: "O'Shea has not trained - he came back with a calf injury from Ireland's game in Cyprus and is doubtful for Saturday so we will see what he's like."