American Football Rugby

If the two sides are tied at the end of the four regular quarters, a 15-minute overtime will be played after a three-minute interval. Each side is allowed one possession and two timeouts. At the beginning of the overtime, the two sides toss a coin to guess who will go first. The side that guesses correctly can choose whether to attack or defend first. Usually in the NFL regular season, if the score of the two sides is still tied after the first overtime, the normal game ends in a tie. The playoffs are elimination games and there must be a winner, so the winner is determined by the sudden death method, and the team that scores first wins the game. This rule has a disadvantage, that is, the team that wins the coin toss often chooses to get possession of the ball to attack, and then advances the line to a closer distance and wins the overtime by shooting, and the other team has almost no chance to get possession of the ball to catch up. In the 2010 season, the NFL made a change to the rules, stipulating that no matter which side must score a touchdown to cause sudden death, if it relies on a field goal, the other side can still take possession of the ball and have a chance to overtake.

College and high school games use the Kansas playoff, which means that no matter how the team that attacks first scores, the other team will still have a chance to catch up with the score. If the game is still tied after the first overtime, the second quarter will be added. If it is still tied after the second quarter, the third quarter will be added... until the game has a winner. If the game goes to the third quarter, the team that scores a touchdown needs to make a 2-point conversion to get extra points (see the explanation in "scoring method" below).