According to multiple sources, negotiations are underway regarding Diogo Leite, with Besiktas keen to finalise a deal with Union Berlin as they look to strengthen their squad for the run-in. The defender has emerged as a top transfer target in recent weeks, and the player's representatives are also believed to be involved in early discussions on personal terms. Whether a deal can be struck remains to be seen, but there is increasing optimism that the transfer could go through in the coming days. Frankfurt, Everton and R. Sociedad may look to intervene if talks continue without resolution. With only 40 goals conceded in 34 (1.18 per game), Besiktas have been one of the stronger defences in the Super Lig this season.. Diogo Leite would be asked to keep that standard and provide dependable cover when needed. Speculation continues to connect Besiktas with Altay Bayindir while no fresh rumours surround Union Berlin. Follow us on Twitter @PlayerSwitchCom and get the latest Besiktas transfer news and rumours direct to your feed.