Mainz have set their asking price for defender Abdou Diallo.

Diallo, who can also play in midfield, is on the radar of Arsenal, Napoli and Borussia Dortmund this summer - with Mainz willing to sell.

Fussball Transfers says Mainz are banking on an auction being sparked.

The Bundesliga outfit are counting on bids kicking off at €30m with Diallo prepared to leave.

Mainz chief Rouven Schroder has confirmed "enquiries" for Diallo, though as yet no offers have been tabled.