More and more freshmen are having an immediate impact on college football.

So much so that "redshirt" can be a four-letter word on the recruiting trail when coaches courting four and five-star prospects interested in playing time.

The list of big names over the last decade who were the big man on campus from the moment they arrived includes:

Maurice Clarett (Ohio State), Larry Fitzgerald (Pitt), Adrian Peterson (Oklahoma), Darren McFadden (Arkansas), Percy Harvin (Florida), Julio Jones (Alabama), Marcus Lattimore (South Carolina), Robert Woods (USC) and Sammy Watkins (Clemson).

Elite skills players can obviously get on the fast track when it comes to developing into college and then NFL stars. However, it's still rare for a recent high school graduate to dominate on the defensive line in a major conference.

But that's what Colorado coaches and players say true freshman nose guard Josh Tupou has been doing since the first day of fall camp.

It's a pretty safe assumption that the 6-foot-3, 325-pound Tupou will be right in the middle of Greg Brown's defensive plans when CU opens the season against Colorado State on Sept. 1 at Sports Authority Field in Denver.

"Josh Tupou is a full-grown man. He might have come out of the womb a full-grown man," said Brown, who is entering his second season as CU's defensive coordinator. "Josh is a lot to handle and he's a fun guy to be around. He's into it. He's a force on the field."

Will Pericak entered the fray at defensive tackle as a redshirt freshman in 2009. But after two full seasons as a starter, CU's new coaching staff still wasn't impressed with the Boulder High School graduate's fundamentals.

"I remember watching him on the first day of drills and going, 'You've got to be kidding me?' " head coach Jon Embree said. "He didn't know how to use his hands right, his footwork was awful, but now when I watch him I see a guy that's got a chance to be an all-conference player."

Pericak, now a fifth-year senior, is now mentoring Tupou and the other freshmen defensive linemen, in an effort to help shorten their learning curve. Tupou and junior Nate Bonsu have been rotating at the other defensive tackle spot.

"He's definitely someone we haven't seen around here in a while," Pericak said of Tupou's talent level. "Josh is not just out there, he's performing. It's interesting to see. ... Being where he is already, three years down the road with this coaching he's going to be a heck of a player."

Tupou didn't even play on defense until his senior year at Buena Park High School in Long Beach, Calif. CU defensive line coach Mike Tuiasosopo knew he had found a special prospect when he laid eyes on the athletic big, who lists playing basketball as one of his hobbies.

"Oh yeah, it's hard to find 6-3, 330-pound nose guards," Tuiasosopo said. "I'm glad he's on our team."

Physically, Tupou is ready to stand up to the Rams' offensive line. The challenge for the coaching staff to develop him into an all-around player so he's ready to deal with USC's offensive line or Oregon's triple option or Stanford's power game.

"Josh is a talented young man. The thing about him right now is he's trying to figure out the college game and sometimes there's lulls in his game," Tuiasosopo said. "The thing that I'm harping on him about right now is attention to detail, knowing what's happening before the ball is snapped.

"I tell my players that great football players are smart football players. He has to pick up the mental part of the game right now."

CU's freshmen are not allowed to speak to the media until after the opener. But when asked independently which newcomers have stood out, the Buffs' experienced offensive linemen provide the same name.

"Josh Tupou is a big dude," said starting center Gus Handler, a 6-3, 295-pound junior. "He's great to go against in practice."

Added 6-4, 295-pound left tackle David Bakhtiari, who might be the program's best player right now:

"Josh Tupou is a big kid and he definitely will be a force to be reckoned with in the future. Even right now he's a good player and his ceiling is through the roof. He has some much potential."

Tupou, whose uncle Viliami Maumau played defensive tackle for the Buffs from 1994-97 and also played for the Denver Broncos, appears to be a huge chip off the old block.

"You never know for sure until a guy gets here and plays," Brown said. "But you know it's good when Mike Tuiasosopo is recruiting him and says, 'You need to check this guy out right here.'

"We think we've hit a home run with this guy."

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