We're all familiar with the many sports terms that have moved into general usage: "par for the course," "slam-dunk," "curveball," "photo finish" and so on.
Curiously, though, every now and then something of the inverse occurs, and we get an expression which is commonly used that has been derived from sport, but never used in sport.
For example, that awful, overdone cliche, "level playing field." Never in my life have I ever heard anyone in sport — that is, somebody actually right there on the level playing field — say, "I'm glad we're playing on a level playing field."
