PSG star Neymar made the move to Paris with an eye on a return to Spain.
Neymar quit Barcelona last month for PSG in a world record €222m move. However, his contract was drawn up with an exit strategy in mind.
Diario Gol says Neymar's deal, while not carrying a buyout clause, does include a Real Madrid option.
It's stated if Real show serious interest in signing the Brazil international, then he must be informed and PSG must listen to the offer.
In the middle of tense negotiations with Barcelona, it was suggested that Neymar was moving to PSG only as a stepping stone to eventually joining Real.
And at 25, the feeling now is Neymar could yet pull on the Merengues shirt in the prime of his career in two years' time.