The Argentina international spent three years at the Bernabeu before he moved to Benfica as part of the Fabio Coentrao deal. Manchester United have been scouting him this season, and were believed to be weighing up a summer bid, but the report claims Real Madrid are now keen to bring him back.
He's been in outstanding form for Benfica, starting all 37 of their matches so far this season, but Real Madrid would not have to pay a premium for a player they let go for just €5.5m in 2011.
The Portuguese paper outlined the intricacies of the potential deal, which is complicated by the part exchange nature of the Coentrao transfer.
Benfica agreed to pay Real Madrid 50 per cent of any fee they received for Garay in the future, which means Madrid would stand to recoup half of any transfer fee paid to the Portuguese club this time around. In effect, Real Madrid would be signing Garay for half the price.
The Argentine has a €20m buyout clause in his Benfica contract. So if they offered €20m, Benfica would be obligated to hand €10m back to Real Madrid because of the 50 per cent clause. Jose Mourinho's side are expected to clear-out several of their defensive players this summer, with Ricardo Carvalho and Raul Albiol set for the chop.
That could free up space for Garay, who would join Sergio Ramos, Raphael Varane and Pepe as the four first-choice centre-backs.
But the Spanish giants will expect competition for Garay at the end of the season. Sir Alex Ferguson is believed to be weighing up a move for a new centre-back, with Garay one of the targets heavily scouted by Old Trafford staff.
Ferguson wants competition for United's current first-team partnership of Rio Ferdinand and Nemanja Vidic, and the 26-year-old Garay has the Champions League experience to step in and challenge for a starting spot straight away.