A derivative of the term Upper Decker, "Under the Bleachers" is somewhat less secretive and much more difficult to pull off. It is the act of taking a poop behind the toilet, under the water tank. Meant to be hidden from view while creating a terrible smell to create the illusion that the toilet could use a serious cleaning.
The dinner party was atrocious, so I took an under to bleachers in their guest bathroom.
I could tell my father-in-law disapproved of me when I entered the bathroom and found that he left a massive under the bleachers.