Stored away in a vault somewhere at the LSU Football Operations Center, there has to be some top-secret formula the Tigers’ offensive coaches use to rotate a stable of talented running backs from game to game and play to play.

Then again, maybe there isn’t.

Which is exactly what Les Miles and his coaching staff want: to keep their tailbacks fresh and keep defensive coordinators guessing who’ll be on the field for any given snap.

It’s such a well-guarded plan that not even the tailbacks themselves know the rhyme or reason behind the rotation, senior Terrence Magee said.

“Your guess is as good as mine,” Magee said when asked how the rotation works. “The depth chart is etched in sand here. You never know who’s going to go (on the field).”

As far as the coaches are concerned, that’s the beauty of having four capable tailbacks like Magee, fellow senior Kenny Hilliard and a pair of highly-touted freshmen — Leonard Fournette and Darrel Williams — to choose from.

As such, Miles, offensive coordinator Cam Cameron and running backs coach Frank Wilson have the luxury of mixing and matching that group on any given running play or pass in an attempt to keep defenders on their heels.

“It could be Kenny and Darrel, or me and Leonard,” Magee said. “You never know who coach Frank is going to put in when we’re on the sideline.”

It could be Hilliard lining up at fullback in front of Fournette, the top recruit in the nation last winter, to form a powerful 1-2 punch. Or even the 230-pound Williams lining up at fullback in front of Fournette, Hilliard or Magee.

Whatever the combination, it’s been good for 15th-ranked LSU.

With the exception of the Mississippi State game, when Cameron had to abandon the running game after falling behind 34-10 in the third quarter, the Tigers have been productive.

Of course, a power ground game has been LSU’s calling card for years. But there were a few questions going into this season despite the return of Hilliard and Magee, and the addition of Fournette and Williams to replace Jeremy Hill and Alfred Blue, who are both now in the NFL.

LSU, which has amassed 1,131 rushing yards in five games, is averaging 226.2 yards a game and 4.6 yards per attempt with 15 touchdowns.

Fournette and Hilliard, who have gotten the most carries with 56 and 57, and Williams are all averaging better than 5.0 yards a carry.

Fournette, who had 122 yards on 18 carries last week in a rout of New Mexico State, has 322 yards and is averaging 5.8 yards a carry with four touchdowns after a slow start to his college career.

Hilliard, who lost a fumble against New Mexico State to earn extended time on the LSU sideline, is next with 298 yards, a 5.2 average and four touchdowns. Williams has 165 yards and three scores; Magee has 144 yards and a touchdown.

Magee said the tailbacks never know when it’s their turn.

“You’re standing there, watch a couple of plays and he (Wilson) calls your number and you run out there,” he said. “You don’t hear the play call, you hear him calling your number.”

In an effort to get each as many carries as possible and have their most productive players in the game, Miles and Cameron have used Hilliard and Williams at fullback.

Hilliard could see more time there in Saturday’s showdown with No. 5 Auburn if Connor Neighbors is still feeling the effects of a concussion SEC Network announcers said he received last week.

They’ve been so productive that Cameron told members of the TV crew he’d like to get three tailbacks in the game with newly minted starting quarterback Brandon Harris, which could be quite a challenge for any defense.

Against New Mexico State, LSU lined up in a “diamond” formation in which Fournette was the deep back with Neighbors and fullback Melvin Jones flanking quarterback Anthony Jennings.

Whoever is in when matters little to the offensive linemen who are there to open up running lanes, center Elliott Porter said.

“We know they’re going to do what they need to do, and they’re going to run hard,” he said with a smile. “We’re very satisfied with whoever’s in.”

But as far as who that might be, Porter, like Magee, said he has no clue as to how the coaches arrive at their decision.

“It depends on how they feel, and who has a hot hand,” Porter said. “It’s whatever coach Miles and coach Frank want to do … I’m with them. We just want our guys to take it the distance every time.”

Follow Sheldon Mickles on Twitter @MicklesAdvocate.