A Spanish high court has allowed a fraud case to be brought against Barcelona star Neymar and asked Manchester City, Chelsea, Real Madrid and Bayern Munich to assist in the inquiry.
Brazilian investment firm DIS, which owned 40 per cent of the Neymar's transfer rights prior to his Barcelona move, filed a complaint which accuses the player himself, his father, Barcelona president Josep Bartomeu and his predecessor Sandro Rossell of being guilty of "fraud" and "corruption" in the Brazilian's 2013 switch from Santos for €17m (£12.2m).
A judge has asked other European clubs who made bids for Neymar to disclose copies of their transfer offers, after DIS alleged an agreement between Barcelona and Santos to give the star a €40m signing on fee diminished his transfer market value.
At the time of his signing, Barcelona said they had paid €57m for the striker, but documents later revealed a further €26m had been paid to his parents.
The club itself is already challenging a case which alleges it avoided paying tax on the undeclared payments.