Comparison of American football and rugby union
A rugby union game is divided into two halves of 40 minutes (or shorter for lower-grade games, and breaks given halfway through each half if playing conditions are considered to be extreme) separated by a half time period of up to 15 minutes in an international match. Most notably, a rugby union game will continue after the scheduled end of a half (half-time or full-time) until the ball becomes dead - any occurrence that would have play restart with a scrum or lineout, or when a team scores. This has led to some "nail-biting" finishes where teams losing by only a small margin work their way towards scoring, and games can go on several minutes over time. Something similar can occur at the end of either half in American football, though usually for only a few seconds of additional time, because a play that begins before the half expires continues until the ball is dead regardless of whether there is any time left on the clock. In both sports, the clock is also stopped during substitutions and for injuries, so the referee does not need to add stoppage time as is done in soccer/Association football. American football games are made up of four quarters of 15 minutes each (less at the high school and youth levels), but the clock stops and starts according to specific rules, so that a 15-minute quarter lasts much longer.
60 Minutes
Starting in the 2012-13 season, in order to accompany a new NFL rule that the second game of an NFL doubleheader start at 4:25 pm, CBS officially changed the start time of "60 Minutes" to 7:30 p.m. Eastern time on Sundays in Eastern and Central Time Zone markets when there is an NFL doubleheader scheduled to air (there are nine doubleheaders during the NFL season – eight during the first 16 weeks of the season, and the final week) to protect against overruns. The start time remains at 7:00 p.m. Eastern time in markets where only a single game is set to air (markets that have only a 1:00 p.m. Eastern time game on single game weeks, and in markets where a home team's NFL game is on Fox at 4:05 p.m., meaning CBS cannot air a doubleheader because of restrictions imposed by the NFL).