Besiktas are interested in re-signing striker Cenk Tosun from Everton.
The 29-year-old spent four seasons with the Turkish club before joining Everton in January 2018 in a deal worth £27m.
Tosun has failed to secure a regular first-team place at Goodison Park under successive managers and has made just five appearances in the Premier League this season.
Besiktas are keen to re-sign Tosun, who scored 41 goals in 96 games for the club, while Russian side CSKA Moscow are also interested in the Turkey international.
West Brom manager Sam Allardyce, who signed Tosun during his time at Everton, was keen to reunite with the striker at the Hawthorns earlier this transfer window.
However, West Brom have since agreed a deal to sign forward Mbaye Diagne on loan from Galatasaray.
Besiktas have also been strongly linked with former Brazil international Hulk, who is a free agent following his departure from Chinese club Shanghai SIPG.
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