Ajax defender Jan Vertonghen has appointed a sports lawyer in an attempt to secure a bonus payment as part of his potential move to Tottenham Hotspur.
The two clubs have reportedly agreed a £9.6m fee for Vertonghen, but the 25-year-old is said to be unwilling to make the move unless he receives 15 percent of the transfer fee.
Vertonghen has a clause in his current contract that entitles him to a share of a proceeds from his departure, however Ajax are arguing that it only becomes active if the transfer fee is a least £15m, according to Inside Futbol.
"I come to a different conclusion to Ajax," lawyer Harro Knijff told Algemeen Dagblad. "Jan is fully within his rights."
It is understood that Vertonghen would rather see out the remaining year on his contract at Ajax and join Spurs for free in 12 months than waive the clause this summer.