Running out the clock
In American football, each quarter of a game is measured with a 15-minute game clock, or 12-minute clock in many high school football codes and the German Football League. A team in possession of the lead and the ball will attempt to use up as much of the game clock as possible in order to bring the game to an end more quickly, thus denying the opposition another chance on offense.
Official (American football)
Because their regular season spans only 17 weeks, the NFL is one of only two major sports leagues in the United States that only pay their officials on a contract basis as opposed to being full-time salaried employees, the other being Major League Soccer. Advantages to this system include being able to eliminate unqualified officials simply by not offering them a contract the following season, where terminating full-time employees would require them to show cause. Critics argue that full-time officials would be free from the distractions of a second job, but proponents of part-time officials point out that the NFL would lose a number of qualified officials because many of them are owners, presidents, or CEOs of various companies. Proponents also argue that there is only one game per week and the regular season is only four months long, and that having full-time officials does not necessarily guarantee that they will make fewer officiating mistakes. The level of training and review in which NFL officials participate makes additional time redundant. In any event, veteran officials can earn substantial salaries for their work. The NFL Referees Association serves as the union that represents officials in the NFL.