Top 25 preview: LSU vs. TCU (Arlington, Texas)

KICKOFF: Saturday, 9 p.m. ET

GAMEDATE: 8/31/13

SITE: AT&T Stadium, Arlington, Texas

TV: ESPN

SERIES: LSU is 5-2-1 against TCU, including a 10-7 victory in the last meeting in 1968.

RANKINGS: LSU No. 12, TCU No. 20

GAME SNAPSHOT

TCU isn't naming its quarterback before Saturday's showdown. Casey Pachall, 15-2 as a starter before he left school to enter a treatment program four games into the 2012 season, isn't guaranteed the job after Trevone Boykin held down the job in his absence. TCU won't have conference defensive player of the year Devonte Fields, who had 10 sacks as a freshman. He's serving a two-game suspension for violating team rules.

LSU returns many familiar faces, led by quarterback Zach Mettenberger, who is operating under the direction of first-year coordinator Cam Cameron against the Horned Frogs' thorny 4-2-5 defense.

KEYS TO THE GAME

LSU is much more of an unknown commodity going into its opener against TCU than it has been the last couple of seasons.

Only three starters from last year's defense are still around after the entire starting defensive line and four other key defenders either ran out of eligibility or left early for the NFL.

The offense has been revamped under first-year coordinator Cam Cameron, and head coach Les Miles has been non-committal about whether leading returning rusher Jeremy Hill will play in the opener or be disciplined further after being suspended in the offseason for a second run-in with the law.

All of that uncertainty is reflected in the Tigers being ranked No. 12 and No. 13 in the major preseason polls after being in the top five prior to the last two seasons.

The talent is on hand for LSU to exceed those relatively modest expectations, but the first indication of how prepared the untested youngsters and the new offense are for prime time won't be known until they face the No. 20 Horned Frogs.

The offense won't stray too far from Miles' comfort zone with a physical running game as its primary component, but the presence of Cameron, a close friend and former coaching colleague of Miles' at Michigan, provides a trust factor in updating the schemes.

"I think that the opportunity to rush the football as we have in the past is certainly there now and you combine that with play action and the things that Cam would bring," Miles said. "I think the advantages are to keep the strength that we've had, but build on it with the ability to throw the football in like situations, in like formations, so the defense cannot determine whether it's run or pass."

Fullback J.C. Copeland said "we're still going to do what we do," but he said he's embraced what Cameron has added.

"It will keep people thinking about what we're going to do," Copeland said. "It won't be the same. There will be a lot of good things. People said we were predictable. We were going to do this and that. We're going to be unpredictable this year because there's no telling what we're going to do. It's going to be a different atmosphere."

A point of emphasis in the offseason and preseason has been to improve the Tigers' "four-minute offense," which is designed to run out the clock by gaining first downs while nursing a lead late in the game. Failure to do so last season cost LSU in two of its three losses as Alabama scored in the final two minutes and Clemson in the final seconds to overcome late deficits.

As for the defense, the Tigers are confident that unfamiliar names will quickly become known for continuing a tradition of suffocating defenses.

"Obviously the number of guys that we lost last year isn't usual -- normally you don't lose that many, but we did," defensive coordinator John Chavis said. "We didn't get caught off-guard. We recruited well before this year and the years before that. But certainly when you lose that many guys, there's going to be some freshmen that are going to have the opportunity to play."

Coach Gary Patterson opted to delay his choice of quarterbacks until game time against LSU.

Casey Pachall, who started the first four games last season before leaving school to receive substance abuse treatment, leads active FBS quarterbacks with a career pass efficiency rating of 163.1.

Trevone Boykin replaced Pachall a year ago and produced mixed results as the Frogs finished 7-6 overall and 4-5 in the Big 12.

"I think both of them can win games," said Patterson, who named both quarterbacks as captains going into the LSU game.

PLAYERS TO WATCH

Tigers

--QB Zach Mettenberger was inconsistent as a first-time starter last season, but did play better down the stretch. Cameron, who doubles as quarterbacks coach, has worked with the strong-armed senior on his mechanics, decision-making and accuracy. Miles has praised Mettenberger for how he has adapted to Cameron's call for a faster tempo in practice (leading to more no-huddle plays in games) and more demonstrative leadership. If Mettenberger provides a more consistent and versatile threat from the passing game, the Tigers could have their most difficult-to-defend offense in years.

--RB Alfred Blue emerged from a crowded and talented backfield to be the starter going into last season and seemed poised for a standout year before suffering a season-ending knee injury in the third game. He was held out of contact work in the spring, but was full-go in preseason camp. Miles said he looks like the same back he was before the injury and Cameron's affinity for passing to running backs could make Blue an even more important weapon.

--DE Jermauria Rasco was held out of contact work until the third and final preseason scrimmage as a precaution after undergoing offseason shoulder surgery. Rasco is being counted on to be an impact edge rusher after serving as an understudy to Barkevious Mingo and Sam Montgomery before they left for the NFL after last season. Rasco appears to have the ability to be another impact end, but he's taking on far greater responsibility than he's had before.

--MLB D.J. Welter missed all of last regular season while being academically ineligible before returning for the Chick-fil-A Bowl. He was inserted as the No. 1 middle linebacker in the spring with the security of knowing senior Lamin Barrow could slide over from the weak side if Welter wasn't up to taking the spot last manned by leading tackler Kevin Minter. Barrow has stayed put as Welter had a solid spring and one of the most eye-opening preseason camps. He's not as physical as Minter, but appears to be instinctive and athletic enough to make the plays.

Horned Frogs

--QB Casey Pachall will attract more attention than anyone on the TCU roster, whether he starts at quarterback or not in the season opener against LSU. Pachall left school after four games a year ago to receive substance abuse treatment, then was allowed to return. He is a terrific passer who sees the field well and avoids mistakes, which the Horned Frogs made far too often last season when they committed 29 turnovers. Expect Pachall to start over Trevone Boykin, although coach Gary Patterson will not officially name a starter until game time.

--RB Waymon James was lost for the season because of a knee injury he sustained in the second game last season. James was coming off a 875-yard season in 2011. He carried 17 times last year for a 9.9-yard average. James approaches 500 pounds in the bench press and 700 pounds in the squat. B.J. Catalon stepped up as a freshman and gained experience, while Nebraska transfer Aaron Green and incoming recruit Kyle Hicks add depth.

--CB Jason Verrett earned All-American honors last season when he led the Big 12 with six interceptions and 22 breakups, yet is only one of several playmakers in a solid TCU secondary. Verrett considered leaving TCU after struggling in his very first game, yet is now one of the nation's top lockdown corners.