Atletico Madrid are seeking permission from FIFA before completing their move for Sporting CP winger Gelson Martins, say Diario AS.
The 23-year-old is one of a number of Sporting stars who has attempted to rescind his contract at the club although it is likely the Portuguese club would be entitled to a fee in any scenario.
The report states Sporting are hopeful of receiving €45m and while he has agreed personal terms at Atleti, they are cautious on proceeding with any formal transfer.
Marca say the Europa League winners are currently in negotiations for the Portuguese international and a deal is looking increasingly likely, with the possibility of striker Luciano Vietto going the other way.
Of Cape Verde heritage, Martins has made 125 first-team appearances for the Lisbon-based giants and has also won 19 caps for Portugal.
The winger netted 13 times in 52 appearances for Sporting last season and is adept on either wing but is mainly deployed on the right flank.