Lazio defender Bastos has been targeted by Dejan Stankovic at Red Star Belgrade in Serbia.
The Angolan defender has struggled to convince coach Simone Inzaghi this season and could be on his way this summer.
So far, the 29-year-old has played 12 times in Serie A 2019-20 and his contract expires in June 2021, leading to speculation regarding his future at the Olimpico.
The centre-back arrived from Russian side Rostov in August 2016 and has played 88 times for the Biancocelesti and contributed nine goals in the process.
Patron Claudio Lotito signed him for €5m four years ago and asks to get at least €6m for his services this time around.
But Il Messaggero has claimed that he could have to settle for half, as Red Star Belgrade hope to complete the transfer by the end of July and Stankovic could get his man on a discounted price.
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