Carlos Tevez's lawyers have written a letter to Manchester City alleging the club have "breached the player's human rights", ESPNsoccernet understands.
At a disciplinary hearing on Friday, Tevez was charged with failing to warm-up in September's 2-0 Champions League loss against Bayern Munich, although a final decision over his punishment has been delayed by City.
The player and his representatives are unhappy with his damaged reputation following his confrontation with manager Roberto Mancini, and have this week issued a letter to City.
City's decision over Tevez's future is unlikely to be swayed by the contents of the letter, which has been described as a "rant" by the club, as the side's hierarchy remain fully behind Mancini, who said post the defeat in Munich that the forward would never play again under his stewardship.
The Argentina international was suspended for two weeks by the club in the aftermath of the alleged incident at the Allianz Arena, and a further six-week ban with a £1.5 million fine looks set to be announced on Monday, subject to approval from the Professional Footballers' Association.
It is expected Tevez will appeal the punishment, and, should he fail, the attacker is prepared to take the case all the way to a Premier League hearing, potentially dragging out a conclusion until the end of the year.
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