updated 5:41 p.m. ET Aug. 25, 2009

SOUTH BEND, Ind. - Competition for playing time and starkly different personalities and running styles didn’t stop Notre Dame freshmen tailbacks Cierre Wood and Theo Riddick from becoming fast friends.

“We roomed here the first day. Ever since then we’re the same exact person,” Riddick said.

Well, not quite the same exact person. At 6-feet, 218 pounds, the chatty Wood is more of a bruising back who also has the speed to run outside. The more reserved Riddick is a slashing runner at 5-10, 195 pounds.

Both, though, have done well enough that they are competing with Armando Allen Jr., Robert Hughes and Jonas Gray for carries for the 23rd-ranked Irish, along with fullback James Aldridge, who could also play some at tailback.

“Both of these guys have made it more difficult for the coaching staff when we make personnel decisions, because neither one of them has played themselves out of contention,” coach Charlie Weis said.

Allen, who led the Irish in rushing last season with 585 yards on 134 carries, a 4.4 yards per carry average, is expected to be the starter when the Irish play Nevada on Sept. 5. But Allen has been slowed by a hamstring injury. Weis said he hopes Allen is well enough this week to start taking the bulk of the load, but nothing is decided.

“We have very good ability and competition at that position,” Weis said.

The running game has been a concern for the Irish the past three seasons, averaging 125.7 yards a game in 2006, 75.3 yards a game in 2007 and 109.7 yards a game last season. Those three season averages combined are nearly 40 yards less than the 350.2 yards a game the Irish averaged in 1973.

So some new blood might be just the answer. Wood and Riddick drew some of the biggest cheers when Weis opened practice to the public on Aug. 15. Wood broke a tackle and got outside for a 35-yard run against the second team defense — matching the longest run for the Irish last season. Riddick showed his ability to change directions quickly with a 13-yard run.

Wood arrived at Notre Dame with more accolades. He was selected to play in the Army high school all-star game and was rated the 10th best player nationwide and the second best running back by Sporting News. Riddick was listed as the seventh best player in New Jersey by SuperPrep.

“Cierre came in with the hype in the recruiting process, but he’s got no leg up on Theo because Theo’s been impressive as well,” Weis said.

Riddick said he’s not intimidated by the attention Wood has received. He’s also not afraid of praising his new friend, describing him as a smooth runner.

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“We call him Cadillac,” Riddick said. “You probably don’t think he’s that fast, but when he starts to get those jets, you see it.”

Wood describes Riddick as explosive.

“He cuts on a dime, and he’s real hard to catch. He’s real fast,” Wood said.

It’s not their running ability that has Weis concerned. The biggest challenge for a freshman back is to learn all the formations and how to pick up blitzes, he said. They need to prove they can do that consistently to earn much playing time.

Riddick, who is from Manville, N.J., and rushed for 1,472 yards as a senior, said blocking schemes have been the biggest challenge for him.

“Because in college, they move around. It’s not like high school where they just stand there and play two or three coverages,” he said.

Wood, who is from Oxnard, Calif., and rushed for 1,632 yards last season, said the biggest adjustment has been the speed of the game.

“In high school everything is just wide-open alleys. Now hole-wise everything is really, really small. So you’ve got to pick and choose where you want to go,” he said.

The two say despite their desire to beat each other on to the field they have no trouble laughing with each other off it. They also defend each other. When told by a reporter that Gray said he’s faster than Riddick, Wood playfully challenged that.

“We’re going to have to race, because everybody’s been saying different kinds of stuff,” Wood said. “We’re going to have to find out who is and who’s not.”

The coaches hope to have that figured out by Sept. 5.

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