Sporting Lisbon are closing in on former Real Madrid goalkeeper Adan, Spanish newspaper AS understands.
The 26-year-old has been a free agent since his contract at Santiago Bernabeu expired a month ago, and he is on the lookout for a new club.
Valencia, Elche, Almeria and Rayo Vallecano were all showing interest in the experienced shot-stopper, but his wage demands proved to be a problem.
Adan was earning around €700,000 per campaign at Real Madrid and he does not want to accept a pay cut.
Nevertheless, AS is reporting that Sporting Lisbon are prepared to meet his demands as they search for a long-term successor to Rui Patricio.
The Portugal international is widely tipped to leave Estadio Jose Alvalade this summer and the Lions believe Adan would be a decent replacement.
While the player continues to train with Castilla, his representatives are in negotiations with Sporting Lisbon and are reportedly close to reaching an agreement.