the.com/touchline

The line that turns coaches into caged animals for ninety minutes straight.

means The boundary line marking the long sides of a football or rugby pitch, beyond which the ball is out of play.

from A straightforward compound of 'touch' and 'line' — in football terminology, the space beyond the sideline was historically called 'touch' (as in the phrase 'in touch'), likely because once the ball crossed it, players were permitted to touch or handle it to throw it back in. The line itself simply marks where the field of play ends and touch begins.

origin
named because players used to touch ball down there
width rule
ball is out only when it fully crosses it
technical area
coaches confined beside it, yelling anyway
length minimum
must be longer than the goal line, oddly specific
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