Stopwatch vs stoppage time – why do rugby and football use different timekeeping systems?

The clock in a rugby union match may significantly underestimate the actual duration of the event.

In the autumn, when South Africa winger Cheslin Kolbe smashed the ball into the stands to seal victory over Ireland, the Aviva Stadium clock and the small graphic in the top corner of the television screen read 82 minutes and 22 seconds.

In fact, with a plethora of televised match official interference, cards, substitutions and injuries, the events stretched over two hours.

However, the match timing is stopped for each major stoppage to allow correct decisions and treatment to be made.

The action continues as players prepare for a rally or kicks into the goal, although referees have “shot clock” time limits that they apply to every aspect of the game.

The advantage to the audience is a clear sense of how much time the chasing team needs to overhaul their opponents.

Rugby rules mean that full time is only called off when the final segment of play has finished, and not automatically when the clock approaches 80 minutes.

The clock “turns red” to show that the next stop is the end of the match adding extra drama to the final play of a close match.

However, rugby authorities also know that the fact that any match can stretch north of two hours is far from ideal for broadcasters, fans or players.

A focus on speeding up the breaks and limited downtime was a key part of World Rugby’s Format of the Game conference in London earlier this year.

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