Niakhate is close to finalising his move to Nottingham Forest and the Tricky Trees have already reached an agreement with Mainz.
The total amount Nottingham Forest will have to pay Mainz will be €10m, while further payments are possible in terms of add-ons up to €5m.
Niakhate is set to receive a three-year contract at the City Ground and now some final steps remain in confirming his signing.
One of the steps remaining is a medical and the centre-back is due to have one today as he heads close to a move to Nottingham Forest.
The plan is for Niakhate to join the Tricky Trees at their training camp in Spain, where the squad arecurrently, if everything goes smoothly.
Niakhate played 30 games for Mainz last season and even got on the scoresheet four times.
Forest manager Steve Cooper will be hoping he replicates his form for his side in the upcoming campaign.
The centre-back is set to become the fourth signing of the window for the Tricky Trees after the arrivals of Taiwo Awoniyi, Dean Henderson and Giulian Biancone.
