flush the mouse

When one, in a fit of anxiety and unsure of the best next steps, makes a rash an ill-advised decision leading to a bad outcome. Originally conceived and made famous on the Tony Kornheiser Show.

I wasn't even sure what state Oakland was in, but I only had two more minutes to submit my bracket, so I picked Kentucky to win. Man, I really flushed the mouse on that one.

Tony: I didn't know what to do with this dead mouse. So, I thought, "I know! I'll flush the mouse."
Michael: Oh, no.