Picket guard

Related to Picket guard: picquets
(Mil.) a guard of horse and foot, always in readiness in case of alarm.

See also: Picket

References in classic literature ?
I went and found Mary, the picket guard half asleep, and longing for her share of the feast.
Likewise, a separate "The Picket Guard," published in March 1862 in the Richmond Dispatch, imagined a guard "at his lonely post" who felt "the foe's first deadly brunt" and died.
Carrie Bell Sinclair, "All Quiet Along the Savannah To-Night," Laura Waldron Papers, Special Collections Library, Duke University; "The Picket Guard," 120.