'A fight ensued the next play' - Bill Parcells had a practice trick so good Cowboys HC Brian Schottenheimer might need to steal it

Brian Schottenheimer has focused on bringing renewed energy to the Dallas Cowboys building. 

That and a culture shift has been the biggest story of the team's offseason amid the new coaching regime. Now, it's only fair to question how much it will all matter once football games are being played, which is why I recently wrote about other changes Schottenheimer could and should bring to the table.

But let me tell you what: We just got the perfect example of how energy could change it all for Dallas in any given week.

Bill Parcells once had Dan Campbell start a fight in Cowboys practice 

Speaking with Ryan Clark from ESPN's This is Football show, former Cowboys wide receivers coach Todd Haley shared an awesome story about Bill Parcells revitalizing a "lethargic" practice. Parcells, in the lead-up to a big game and probably Tony Romo's starter debut (Haley is unsure), intentionally forced his players to fight.

The key to it all? Then tight end and now Detroit Lions head coach Dan Campbell.

"Practice on a Wednesday was going bad and you could see coach Parcells getting heated up, he was not happy with the way anything was going, there was no energy," Haley told Clark on the show.

"I see him call Dan (Campbell) over to the side and say a couple of words to him, (. . .) Parcells with his arms crossed walked over to me and said 'watch this, Todd', a fight ensued in the next play," Haley added.