out on one's feet

Etymology
From the sport of boxing, referring to fighter who is too stunned to fight effectively, but who does not collapse to the canvas.

Adjective

 * 1)  Standing erect but not consciously aware of one's surroundings, or only minimally aware, and having little or no ability to control one's bodily actions, as a result of physical injury or exhaustion.
 * 2)  Stupefied; dazed; nonfunctional.
 * 1)  Stupefied; dazed; nonfunctional.
 * 1)  Stupefied; dazed; nonfunctional.
 * 1)  Stupefied; dazed; nonfunctional.