This is Wily Peralta falling down, clearly forgetting how feet or ambulatory motion work.
Pop quiz: Somebody trips over their feet running and hits the grass. You decide to describe this moment to a friend or family member. Which phrase would you use? Maybe you'd say "He ate it" or "He tripped." Perhaps you'd posit that he "stumbled" or simply "fell."
Our guess, you probably wouldn't say this.
Brewers' Wily Peralta just took a huge dump running onto the field for pregame introductions.— Joe McDonald (@ESPNJoeyMac) April 4, 2014
Maybe this doesn't refer to the fall at all, who are we to say?