NEW YORK — The NFL has filed legal documents as a precursor of its planned appeal of a federal judge’s ruling to vacate the four-game suspension of Tom Brady.

The 200-page filing with the 2nd U.S. Circuit Court of Appeals on Thursday serves as a preview of the strategy the league will use to try to overturn U.S. District Judge Richard Berman’s decision to vacate the punishment handed down by NFL Commissioner Roger Goodell.

In a pre-argument statement, NFL attorney Daniel Nash outlined three grounds for an appeal: Berman used the wrong federal law to overturn the decision; he erred by disagreeing with Goodell’s interpretation of the NFL’s collective bargaining agreement; and that he shouldn’t have disagreed with Goodell’s rulings.

The NFL announced on Sept. 3 – the same as Berman’s ruling – that it would file an appeal.

Brady was suspended and the New England Patriots were docked $1 million and two draft picks after a league investigation found the team provided improperly inflated footballs for the AFC title game against the Indianapolis Colts in January.

If the NFL wins its appeal, Brady would have to serve the suspension. But legal experts do not think the appeal will be resolved until after the season.