National Football League rivalries

As with all sports leagues, there are a number of significant rivalries in the National Football League. Rivalries are occasionally created due to a particular event that causes bad blood between teams, players, coaches, or owners, but for the most part, they arise simply due to the frequency with which some teams play each other, and sometimes exist for geographic reasons.

Purely geographic rivalries are rare in the NFL, since crosstown rivals do not play each other nearly as often as in other leagues that have more games (and therefore more opportunities to play other teams). For example, Major League Baseball teams face each league opponent at least six times in the regular season, and within a division as many as 19 times. In recent years, the NFL changed its scheduling formula to ensure every possible matchup happens within a four-year span, not counting pre-season games or the Super Bowl. A main factor in the fact that crosstown rivals are almost always in opposing conferences is history: in the three current markets (New York/New Jersey, Los Angeles, and San Francisco Bay Area) that have two NFL teams, all have one team (Jets in New York, Raiders in Oakland, Chargers in Los Angeles) that was a member of the American Football League. As part of the AFL–NFL merger, all AFL teams had to be retained, even if it meant multiple teams in one metropolitan area. The newly merged league opted not to go through an extensive geographical realignment, and instead, the AFL formed the basis of the AFC, and the old NFL formed the basis of the NFC; as a result, each team ended up in an opposite conference from their crosstown rival. This allowed the combined league to retain both existing television partnerships of each league—NBC for the AFL/AFC, and CBS for the NFL/NFC—instead of choosing one or the other (ABC joined the mix in 1970 with Monday Night Football).

Games between opponents in the same NFL division. Since 2002, there are 32 teams in eight divisions of four teams each. Each team plays each division opponent twice in the regular season (once at home, once away) for a total of six regular season games out of 16 total. Occasionally, two teams will play three times in a year if they meet again in the playoffs.

Teams do not play a given conference opponent from outside their division more than once during the regular season, however they may meet again for a second time in the playoffs. The NFL schedules divisions to play against each other on a rotating basis, so that every team from one division will play every team from another division, for a total of four games per team. Each team will also play one team from each of the remaining two divisions within the conference that finished in the same divisional standing position in the prior year—for a grand total of 20 conference games. Conference games are often important, as a team's record in common games, as well as its overall record against its conference, is sometimes used as a tiebreaker for playoff seeding at the end of the regular season. Also, many regular season opponents have met again in the playoffs, and the result of a regular season game can affect where the playoff game will be played. Conference rivals will play each other at least once every three years in the regular season, and as frequently as once every year depending on record, and can play each other in the preseason.

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