Plus-One system

The Plus-One system is a method of determining the National Champion in the Football Bowl Subdivision (formerly Division I-A) of NCAA football in the United States where the participants National Championship Game are dependent on the results of at least two bowl games. The format can take on the form of a 4-team playoff, where two bowl games act as semi-final games, and the winners of these games participate in the National Championship Game. Alternatively, the participants of the National Championship Game can be chosen after the conclusion of the normal bowl season; in this situation, there are no semi-final games, and the top two teams would be ranked based on the outcomes of the bowl games.

The current method of postseason play in the Football Bowl Subdivision NCAA football in the United States is a 4-team playoff, which can also be thought of as a Plus-One System, since the National Championship game is played after two bowl games hosting semi-final games. It is one more round of games than the Bowl Championship Series (BCS) system, which was used through the end of the 2013 season. The system first took effect at the conclusion of the 2014 season during the first College Football Playoff.

The BCS used a formula based on polls and computer rankings to assign teams to postseason games, known as bowl games. The teams that were ranked #1 and #2 nationally, according to the formula, were placed into the BCS National Championship, and the winner was crowned champion for that season.

The BCS was a very divisive issue in college football. Opponents of the system argued that it was unfair to automatically assign teams to the National Championship, because it was impossible to determine the two top teams without some form of a playoff. BCS supporters argued that a playoff would minimize the importance of the regular season and would lessen the intensity of rivalry games, a staple of college sports, and that a playoff would be too time-consuming for student athletes who have scholastic obligations in addition to their athletic commitment.

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