It's over a controversial banner displayed by the club's fans last season.
Nottingham Forest owner Evangelos Marinakis has confirmed he is suing fellow Premier League club Crystal Palace.
It's over a controversial banner displayed by the club's fans last season depicting him holding a gun to midfielder Morgan Gibbs-White's head.
It also read: 'Mr Marinakis is not involved in blackmail, match-fixing, drug trafficking, or corruption.'
Marinakis has consistently denied any wrong doing in relation to such allegations.

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