Goalkeeper Steve Mandanda has reportedly claimed that he has been treated unfairly by Crystal Palace.
Last summer, Mandanda ended his long association with Marseille to move to Selhurst Park, but after suffering an injury he failed to earn his place back in the side and his last first-team outing came in November.
It has been reported that Marseille are keen on a reunion with the French international, but Palace are allegedly not prepared to accept their cut-price offer of £1.5m.
According to The Sun, both factors have led to the 32-year-old opting against returning for pre-season training when Frank de Boer is confirmed as Sam Allardyce's replacement.
It has been claimed that Palace are demanding £4m for his signature, but it remains to be seen whether Marseille are prepared to at least double their initial offer.
Mandanda made 441 appearances in all competitions during his time at the Stade Velodrome.
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