To maximize TV ratings, as well as to protect the NFL's ability to sell TV rights collectively, games televised on ESPN or the NFL Network are blacked out in each of the primary markets of both teams (the Green Bay Packers have two primary markets, Green Bay and Milwaukee, a remnant of when they played some home games in Milwaukee each season, see below) under syndicated exclusivity regulations as the league sells via broadcast syndication a package featuring that team's games.
However, the home team's market must be completely served by the station and that broadcast can only air if the game is sold out within 72 hours of kick-off.
On November 8, 1987, the first NFL game aired on ESPN was played between the New England Patriots and New York Giants.
Technically, the game was only simulcast in the Boston market, with a separate broadcast produced for the New York market by ESPN sister property WABC-TV – at the time, WABC's union contract prohibited non-union workers (like those of ESPN) from working on live events broadcast on the station.
This marked the only time since the AFL–NFL merger that a regular season game was locally produced for TV.