Barcelona are suing Neymar for 8.5M Euros over the world record transfer to Paris St-Germain.
Neymar made the 222m euro (£200m) move to the French clubin August after buying out his contract.
His former club Barcelona now want him to return a renewal bonus he was paid when he signed a new five-year deal just nine months before forcing through the move.
Paris St-Germain later responded to say they were “surprised” by Barcelona’s statement, adding: “The club repeats that, along with Neymar Jr, it strictly respected all applicable laws and rules and can only regret, once again, the attitude of FC Barcelona.”
The lawsuit was submitted on 11 August to the Labour Tribunal in Barcelona.
Following the transfer, Barcelona announced the club was withholding a further 26m euro (£23m) loyalty bonus from the player.
Neymar criticised the directors of the club on Sunday after scoring twice on his home debut for PSG in a 6-2 win over Toulouse.
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