Mainz captain Moussa Niakhate has emerged as a target for Premier League clubs.
The French defender, reports the Telegraph, has West Ham United, Everton and Newcastle United all following him ahead of the summer market.
Niakhate has a deal to 2023 and is likely to be cashed in by Mainz at the end of the season.
West Ham are particularly keen, with doubts over the future of Angelo Ogbonna.
Mainz will be prepared to sell Niakhate in the region of €9-10m.