The extent of Smith's injury was not immediately known, but Nutt didn't sound too optimistic when asked about it.
"I hope it ain't bad," Nutt said. "... You've got to hold your breath with him."
Nutt spoke earlier this week on the importance of keeping Smith on the field. The redshirt freshman was slowed down last season after he pulled his right hamstring on the third day of preseason practices.
Smith went down Tuesday during team drills toward the end of practice. Trainers examined the running back before he limped off the practice field.
Meanwhile, freshman Van Stumon worked with the offense after coaches decided to move him from linebacker to fullback.
"He can go a lot of positions. He can go linebacker, defensive end or fullback," Nutt said of Stumon, a North Little Rock native. "So, we wanted to go fullback right now and experiment with that for a little bit, for about a week and let's see how that goes."
Quarterback Casey Dick didn't get any work during team drills and instead watched as junior Robert Johnson and freshman Mitch Mustain took all the snaps.
Nutt said Dick was healthy, but the coaches wanted to change things up some for the three quarterbacks who are competing for the starting job.
RB Smith injured
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