Portsmouth have made a complaint to authorities over Genoa's failure to pay a £1.2million (€1.55m) instalment of Kevin-Prince Boateng's transfer, according to Sky Sports News sources.
It is understood Portsmouth have yet to receive a penny from the Italian club for a player who is now on loan at AC Milan.
Sky Sports News understands that Genoa failed to pay a first instalment of €1.55m on the due date of 5th September.
A second instalment is due to the Championship club in just over a week's time on 5th October.
Swanson understands that Genoa officials initially blamed the delay on their administrative department, after failing to have the correct bank account details, and a series of furious exchanges between the clubs has led to Portsmouth questioning Genoa's integrity.