Mack Brown must love the song lyrics, “Yesterday’s gone.”

For those who wonder what has changed between Mack I and Mack II as the Tar Heels football coach, there is quite a difference. After leaving Carolina with a top ten program in 1997, Brown spent 15 seasons at Texas rebuilding one of the proudest college football empires in the country.

If you want to know what happened to Brown between his stints at UNC, just go to his Wikipedia page for these salient bullet points: A won-lost record of 158-48 at Texas — which together with his 86 previous wins at Carolina, Tulane and Appalachian State make Brown the winningest active coach in the country (yes, that includes Nick Saban).

After winning 10 games in his last two years coaching the Tar Heels, he had nine consecutive seasons at Texas with 10, 11 or 12 victories; in all, 20 straight winning records and 18 bowl teams that played in two national championship games, winning the old BCS title in 2005.

He left UNC making less than $1 million and finished at Texas making more than $5 million, with bonuses that left him a very rich man when he retired after the 2013 season. He only returned because he missed coaching.

He wowed fans and media at his re-introductions, but really showed the inner workings of a football CEO in his 40-minute presser the day before spring practice opened. Reading from a sheet with parts highlighted in yellow, Brown went through every step of how to run a program.

He explained how he and his coaching staff would begin teaching their new players and what he expected of them, on and off the field. The off-shoot: those who play will have earned it in practice and their private lives; those who stay on the field will have earned it in games. When some are not playing, he will point out their mistakes and say, “Don’t get mad at the coaches, that is why.” And Mack will challenge them to get better.

His media relations staff writes emails that tell members of the press where to go, where to park and what to do during practice. Those with cameras will be asked to “focus on individuals or small groups and refrain from capturing video and images of formations and any signals.”

If it’s a closed practice at UNC’s new state of the art inside facility, the media will be told where to gather before the doors open and please don’t peek in the windows while drills are going on. Details upon details.

Mack II is back as a College Football Hall of Famer with five years as an ESPN analyst before coming out of retirement. Yesterday’s gone as he begins rebuilding a program but also the winning tradition of yesteryear.