Bolton Wanderers have joined Madrid-based Unión Adarve, who play in the fourth tier of the Spanish football pyramid, in reporting Barcelona to FIFA following their signing of Marcos Alonso from Chelsea last summer.

The defender played for the two clubs earlier in his career and both claim they are due a development fee after his move to Barca.

FIFA have already heard the cases put forward by Barça and Adarve though are yet to make a final judgment, says AS.

FIFA's compensation system means a set percentage of any player's transfer fee must go to clubs he played for at youth-team level after the age of 12. Alonso spent the majority of his youth career at the Real Madrid academy but also turned out for Adarve, while he later left Los Blancos to sign for Bolton when he was 19, an age at which he still qualified as a youth player.

The Trotters, currently in League One, are insisting they are due training compensation. This is disputed by Barcelona as they have declared Alonso a free transfer from Chelsea. Neither Bolton nor Unión Adarve believe that to be the case, however.

Instead, the two clubs say Pierre-Emerick Aubameyang's move to Chelsea was part of the Alonso deal and are insisting the €12m fee the Blues paid for the striker is significantly below his market value, which means that Alonso must also have been included in a cash-plus-player transfer.