boundary rider

/B AW1 N D ER0 IY0 R AY0 D ER0/
noun
  1. 1

    A person employed to travel along the boundary of a station, to check and maintain the fencing.

  2. 2

    A commentator on Australian rules football games who reports from the boundary of the field of play, and interviews players on the interchange bench as well as coaching and medical staff.

Source: https://en.wiktionary.org/wiki/boundary%20rider