Posted by ESPN.com's Tim Griffin
Earlier in spring camp, Nebraska I-back Roy Helu Jr. predicted that competition for playing time among the Cornhuskers would be "cut-throat" this spring.
While there have been no incidents reported -- yet -- the battle for the starting job at I-back for the Cornhuskers might be one of the most intriguing in the Big 12.
A bigger, stronger Helu was involved in a tight battle with skinnier Quentin Castille for playing time before Helu tweaked his hamstring last week. It's kept him out of practice since then, although it doesn't necessarily worry Nebraska coach Bo Pelini.
"We're in no hurry right now with Roy," Pelini told reporters last weekend. "It's just not the time of year to rush him back. He had a phenomenal spring when he was going. He's had a great winter. More importantly than just finishing the spring, we want to him to be healthy as he's quickly as he can so he can get back into his training and offseason work.
His injury has opened a chance for Castille, who is poised to receive much of the action at Saturday's Red-White scrimmage to finish off Nebraska's spring practice.
Before Helu's injury, the position was shaping up as an intriguing one as both primary backs had transformed themselves since the end of the 2008 season.
Helu gained 24 pounds that he feels will make him a more powerful runner between the tacklers. He's now up to 222 with no resulting loss of speed after weighing 198 last season.
"To be honest, it's kind of a blessing and a curse. Every time I look in the mirror I look at myself now," Helu said. "I feel faster and more explosive and there's more muscle there than fat."
While Helu has bulked up, Castille has slimmed down. He now weighs about 235 and said he feels quicker and sleeker than at any previous time in his career.
"It was kind of my goal, but not really," Castille said. "I guess it just happened with the conditioning and the weight lifting, but I feel stronger and faster, too."
Together, the transformed I-backs could emerge into one of the nation's best combinations and a potentially lethal offense force for the Cornhuskers.
Helu bulked up late last season and the results were seen in the Cornhuskers' late charge. He rushed for at least 100 yards in three of Nebraska's final four games -- including a career-high 166 against Colorado -- to help the Cornhuskers claim that game and earn a share of the Big 12 North title.
The late charge enabled Helu to finish with a team-leading 803 yards and become the first Nebraska running back since 2000 to average at least 6 yards per carry.
Castille saved his biggest game for last. After dropping about 10 pounds because of a late-season injury, the sleeker Castille gashed Clemson for a game-high 125 yards in the Cornhuskers' comeback victory in the Gator Bowl. Included in that total were career-best runs of 58 and 40 yards as he emerged as an imposing breakaway threat along with his substantial abilities as a move-the-pile ball-carrier.
That late surge enabled Castille to produce 467 rushing yards to rank 19th in the conference despite his limited playing time.
It wasn't exactly the golden days when Mike Rozier was running behind Dean Steinkuhler, but it wasn't far from it. The Cornhuskers piled up 211.6 yards rushing per game over the second half of the season to become the backbone of the team. Earlier in the season, the Cornhuskers failed to produce 100 rushing yards in three of the first five games of the season.
And while offensive coordinator Shawn Watson still favors a balanced pass-run ratio, it almost a foregone conclusion that the Cornhuskers will lean more on the running game this season. Nebraska will be breaking in an untested quarterback throwing to a largely untested group of wide receivers that was thinned a little earlier this week when Niles Paul was suspended.
Helu's injury has temporarily halted the I-back competition for the rest of the spring. But the positional battle will shape up during the summer as one of the team's biggest strengths headed into the season.
Nebraska coaches are so confident about their combo of Helu and Castille that they moved Marcus Mendoza from I-back to wide receiver where he's likely to see playing time immediately. Mendoza likely could have been a productive ball-carrier on many Big 12 teams.
And while chatter of the message boards about the battle for the I-back position has been intense since the end of the season, Castille expects both he and Helu will receive many opportunities to help the team next season.
"Me and Roy just go out and there play," Castille said. "I don't know if it's going to be one of us who will steal the job from the other. He brings something totally different to table than I bring. I'm anxious to see what will happen during the season when both of us are playing."