The football tampering scandal dubbed "Deflategate" could hit $20 million in legal fees, according to ESPN.
The NFL controversy involved allegations of tampering with footballs by the New England Patriots in the AFC Championship game against the Indianapolis Colts in Jan. 2015.
The league announced in May 2015 that it would suspend Patriots quarterback Tom Brady for four games of the 2015 regular season for his alleged part in the scandal.
The Pats were also fined $1 million and docked two draft picks.
ESPN says according to a survey of three lawyers, who have worked for leagues, experts believe no matter what happens in the court of appeals on Thursday, legal costs could eventually hit $20 million.
Three federal judges will hear the NFL's appeal of the lifting of Brady's four-game suspension in Deflategate. Arguments will take place Thursday in New York City. The judges will decide whether a lower-court judge was correct to negate Brady's suspension.