Leeds United are facing an FA probe relating to the loan signing of Adryan last season.
The Yorkshire Evening Post reported last night that the FA have summoned owner Massimo Cellino for a meeting, concerned the Brazilian is part-owned by a third party.
Cellino maintains Leeds have done nothing wrong and Adryan is fully owned by Brazilian club Flamengo.
Third party ownership is banned in England, and as of this summer it will also be outlawed by European football's governing body UEFA.
The news casts yet another shadow over troubled Leeds United, who just this week welcomed owner Cellino back from a Football League ban, owing to a previous tax conviction.
The worst case scenario for Leeds is a points deduction for next season.
QPR were involved in a similar case regarding Alejandro Faurlin in 2010/11, but escaped a deduction and were hit with a £875,000 fine instead, reported the BBC.
West Ham also escaped a deduction in 2007 relating to the transfers of Carlos Tevez and Javier Mascherano, instead being fined £5.5 million, per the BBC.
Deducting points in both cases would have changed the outcomes of promotions and relegations in respective seasons.
This season Rotherham United were deducted three points for fielding an ineligible player.
A fine is more likely for Leeds if found guilty based on precedent, but all options are likely to be on the table, and a further transfer ban, on top of their recent one in January, is another scenario the FA could consider.