Corey Grant Arkansas

Arkansas safety Alan Turner (27) stops Auburn running back Corey Grant (20) during the second quarter at Razorback Stadium Saturday, Nov. 2, 2013, in Fayetteville, Ark. (Julie Bennett/jbennett@al.com)

ROME, Georgia -- Tim Horton is not sure if he has the answer.

The Auburn running backs coach paused for a moment Monday outside a Northwest Georgia Auburn Club event at State Mutual Stadium here when asked who walked out of spring practices as his top running back.

Upon reflection, Horton looked down to his right hand, placed his thumb beneath his index finger and flipped an imaginary coin.

"I'm not trying to be smart," Horton said. "I'm being honest. It would be one of the two old hands."

The two old hands are his two lone seniors: Cameron Artis-Payne and Corey Grant. The veteran SEC assistant coach is happy with the fact that he doesn't have to make a call immediately, especially with two freshmen on their way to campus and a redshirt freshman, Peyton Barber, recovering from a high-ankle sprain following a marathon of 15 practices in the spring.

The job of finding a replacement for Heisman finalist Tre Mason in the backfield is a tough one, but Horton feels like he has options with Artis-Payne, Grant and Barber.

"On campus right now we've got three guys that I have a lot of confidence in," Horton said. "Sometimes when you say you've got three guys it really means you don't have any, but for us I think we've got three guys we can go to war with and win in the SEC."

The hole Mason leaves is not small. He broke Bo Jackson's single-season rushing record at Auburn, after all, and accounted for 1,816 rushing yards and 23 touchdowns, tying Tim Tebow's SEC scoring record.

Even more impressive is how Mason accumulated those yards. The NFL-bound tailback amassed 45 percent of his rushing yards after contact, Horton said.

"We have to replace Tre Mason, in my opinion the best running back in the nation last year," coach Gus Malzahn said last week. "We have two seniors we feel very good about, Peyton Barber's a younger guy, Roc Thomas is coming in. So we feel like we have a lot of good options and we'll see what happens."

Horton has a variety of options, but the battle will not ramp up until blue-chip freshman Roc Thomas arrives on campus.

Artis-Payne is bulldozer between the tackles and has proven to be an able option in the passing game and in space after rushing for 610 yards and six touchdowns last season. Grant is the fastest tailback on the team (he rushed for 647 yards while averaging 9.8 yards per carry) and is still trying to prove his worth as a between-the-tackles runner in addition to his strength as the Tigers' primary jet-sweep threat.

Barber was impressive in the spring but was injured on his first carry in Auburn's A-Day spring game on April 19. He is expected to make a full recovery before the start of fall camp in August.

The question is whether Thomas can adjust to playing college football. A new NCAA rule allowing assistants to break down film and work with players for two hours each week during the summer should help his progress.

"Obviously, and you've seen it, too, his video is really impressive," Horton said. "He's really a good, good player. The thing that you don't know as a coach is how quick can he learn it? As a coach, I always say that's my job. It's my job to be a good teacher and teach him as fast as he can, and so that's the part that you just don't know about but, again, with the new rule like it is, I think it just helps him have that opportunity."