Sao Paulo and Rodrigo Caio are in formal negotiations for a move to Napoli, confirmed his representative.
The defender was in Naples last week to pick up an Italian passport, making him more appetising to Italian clubs.
Now Cristian Sfara has given CalcioNapoli24 a copy of a letter from Sao Paulo “authorizing him to hand and act for our contracted professional football player, Rodrigo Caio Coquette Russo, to find a possible contract concerning a transfer for SCC Neapel.
“The authorization is valid until the 31st of August 2016.”
Sao Paulo previously confirmed the centre-back was available for €10m.
He has been linked with Sevilla and Milan, among others, but Napoli have paperwork confirming they are in negotiations.
Napoli are also widely reported to have agreed terms with Torino this evening to take defender Nikola Maksimovic for €27m plus Mirko Valdifiori on loan with obligation to buy for €3.5m.
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