Mauro Icardi is suing Inter Milan for discrimination, claiming €1.5 million in damages and to be allowed back into the first-team fold.
In published extracts from the legal document Icardi alleges the club took "clearly discriminatory" action against him.
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The forward said that apart from being dropped from advertising campaigns and the team photoshoot for this season's new jersey, he was also forced to train separately from the first team (after warming up together) and excluded from specific training sessions for forwards, directed by Inter coach Antonio Conte.
Icardi also said he was excluded from the team's WhatsApp group which is where players are told about the training schedule. Instead, the information on the timings is being sent to him privately.
It was also highlighted that the No. 9 jersey was taken away from Icardi "despite him having signed 124 goals in that jersey in the past five seasons."
That jersey was given to Inter's new record signing, Romelu Lukaku. Inter also recently signed another forward from Manchester United, bringing in Alexis Sanchez on loan.
Icardi is suing to be allowed back into the full training sessions and claiming damages amounting to at least 20 percent of his salary, approximately €1.5m.
"It's not a question of money. What matters to Icardi is to be an integral part of Inter's plans," Icardi's lawyer, Giuseppe Di Carlo, told Sport Mediaset on Saturday.
"The request for damages is a necessary consequence of the legal action. It's an obligatory formula. It's not a personal initiative by the player. The document would have been incomplete without specifying immediate damages of not less than 20 percent of his annual salary."
Sources told ESPN FC on Friday that Atletico Madrid are negotiating a deal to sign Icardi on loan with the option to buy for €70m.
He has been linked with moves to Juventus and Napoli but, according to ESPN FC sources, would be delighted to join Atletico as he and his family are keen to move to Madrid.
The problems with Icardi, who was Inter's star forward, began in January in a contract dispute. The Argentine was then stripped of the captaincy.
Shortly after that Icardi said he had a knee injury, although the club has said tests did not reveal any problem. There then followed a six-week exile before Icardi eventually resumed training, returning to the field for the last weeks of the season.
According to Italian media reports, Napoli and Monaco have been interested in 26-year-old Icardi but he has rejected every opportunity presented to him so far.
"Everything has been done in the most correct way possible," said Conte, who took over at Inter in the offseason. "People have been talking about this person for eight months and I don't want to get into it. We should be totally concentrated on this season, instead others are still the protagonists and not those who are playing this season.
"But it continues to be no disruption to us ... for other people it's more important to get into other situations but we are focused on what happens on the pitch."
Inter won their opening Serie A match 4-0 last week, against newly promoted Lecce. It visits Cagliari on Sunday.