You hear all the time how players will run through a brick wall for coaches they respect and admire.
But as Notre Dame back Cam McDaniel found out the hard way, it's impossible to get through a gauntlet sled that is turned around backward.
This soon-to-be classic clip from Notre Dame practice features Coach Brian Kelly leading his running backs through a drill.
When someone suggests the sled is backward, Kelly responds "No, it's not backwards!" and then goes into coach-talk about how he's looking for the "one step, slide cut here."
McDaniel then charges into the sled and is stopped colder than New York Jets' quarterback Mark Sanchez was last year by the rear of his own offensive lineman.
For Irish players, it must have been a flashback to last year's title game against Alabama.
The good news is Notre Dame opens the season against Temple's defensive front, which isn't a backward gauntlet sled. The Owls finished No. 100 nationally last year against the run.