Manchester United may reportedly have to pay £127m in order to complete the signing of Napoli defender Kalidou Koulibaly.
During the last three transfer windows, United have been heavily linked with a move for the Senegal international, who has established himself as one of most highly-regarded centre-backs playing in Europe.
Last month, it was suggested that the Premier League giants were prepared to push through a big-money deal for the 28-year-old in the summer.
However, according to Corriere dello Sport, United face having to pay a larger fee than expected due to a release clause being activated in Koulibaly's contract.
The report says that the figure becomes relevant in June, although whether Napoli are in a position to demand that sum could depend on whether they qualify for Europe.
Koulibaly, who has a deal with the Italian outfit until 2023, is also said to be a target for Paris Saint-Germain.