"It's so big because the guy gets you out of so many bad calls," the first-year Vol coach said recently. "Every call's not going to be great. You see it on film all the time: They don't block the Will linebacker because they're overloaded to that side, they didn't make the right call upfront and the (defender) is sitting there for a two-yard loss, but the guy spreads it out and makes 10 yards, and everybody thinks it was a great play call.
"They're very valuable to you, especially in short-yardage, if you have a great back. The play call gets you to a certain point, then the the player gets you to the next point. When you get a great back those 10-yard runs become 60-yard runs."
So, what separates the great back from the good back? The ability to elude that last defender.
"You're not going to block everybody," Kiffin said. "When you block it right - you've blocked everybody and there's a free safety sitting back there at 10 to 12 yards - here comes recruiting. At this point it's not coaching. Did we recruit the right guy? One guy is going to get tackled for a 10- to 12-yard gain and the other guy's going for a 60-yard touchdown. It's so critical to have a superstar back, and I hope we do."
The folks at Scout.com think the Vols have a superstar back. They rated freshman Bryce Brown the No. 1 prospect in America last season.
"I don't get to see any of (the voluntary summer workouts) but I can tell you this: When you walk by Bryce, he looks like the real deal," Kiffin said. "He's 218 pounds right now and he looks like a guy who's been in the NFL for a few years. David (fellow rookie David Oku) looks more like the normal freshman coming in. He's skinnier.
"Bryce is built up really well and he's got that superstar walk, that presence, that swagger."
Brown gained some unwanted notoriety last winter because of a self-styled "manager" who charged $9.95 per month for on-line updates of Brown's recruitment. This led some folks to figure the player was a prima donna.
"I think maybe through recruiting some people got the wrong image of Bryce," Kiffin said. "When you spend time with him - as you guys (in the media) will - I think you'll love him.
"He's a very special guy. He's a great student. I think he was a 3.7 GPA who graduated early. He's very dedicated. He's very serious and very focused about being great."
History suggests that if Bryce Brown becomes great, there's a chance Tennessee eventually will become great, too.