he official must ask himself: Did a ruck form? When did it end? Were players guilty of being off-side? What happens when it collapses? Did play continue to the next phase?

What's a rugby game without rucking? Right? Skillful teams use the situation effectively, similar to gridiron football runners using blockers to their advantage.

And this "prodical son" in rugby takes place often in a game, spontaneously evolving so often that game statisticians cannot keep count.

How does it develop?

The beauty of a well-played ruck is in the ball crawling back on the ground without the use of hands. When it's finally cleared for pickup in an offensive play, the referee must have secured the off-side lines to provide the space for continuation of the play.

In essence, the ruck facilitates continuity. The problem for the referee arises when he's not in a position to see the formation of the ruck. Failure to see its development causes unnecessary stoppages and disadvantages the team that observes the rucking laws.

Here's a simple example of the ideal ruck:

Continued...