This is the fourth in a series of articles ranking the Sun Belt Conference's football teams unit-by-unit.
In a league where so many offenses rely heavily on three- and four-receiver packages, offensive linemen have their work cut out for them.
Teams who can't protect their quarterbacks or open lanes for their running backs will do little more than frustrate their coaches and fans.
The Sun Belt Conference's offensive lines stack up like this.
1. North Texas
A couple of schools return four of their five starters up front, and they happen to be 2009's top two SBC rushing teams. UNT attains the top spot here because, unlike Middle Tennessee State, they return four starters in the spots they're used to playing.
UNT's line was in fast company last season. They ranked in the top 12 nationally in sacks allowed, allowing only 12 all season. The Mean Green also placed in the top 30 in rush offense and the top 51 in pass offense. Boise State was the only other team to manage all those feats at once.
Second-team All-SBC tackle Esteban Santiago leads the unit from the right tackle position. The 6'3", 296-pounder isn't a mammoth presence, but his versatile game is effective on both run and pass plays.
On the left side, senior Victor Gill has had issues staying in the lineup, battling assorted injuries and missing a couple of starts in 2009.
Despite the bumps and bruises, Gill actually managed the line's best grade last season, at nearly 90 percent, and led the unit with 44 knockdowns.
Left guard Kelvin Drake made a smooth transition from the center spot, where he was a second-team All-SBC performer in 2007.
Towering junior J.J. Johnson (6'6", 283 pounds) took over from Drake at center in 2008, and has started every game since.
The only new starter will appear at right guard, where sophomore Coleman Feeley appears ready to return after a redshirt last year. Feeley's known as a bruising run blocker, which will be highly appreciated by Sun Belt rushing leader Lance Dunbar.
Off the bench, junior Matt Tomlinson has a pair of starts under his belt, replacing Gill on the left side against Alabama and Middle Tennessee last season.
Sophomore Aaron Fortenberry is listed as the backup at both center and right guard, and has the size (6'4", 288) to play tackle if absolutely necessary.

2. Middle Tennessee State
Like North Texas, MTSU returns four starters from last year's potent line. Unlike the Mean Green, the Blue Raiders have one of their four adapting to a new position.
The loss of All-SBC center Mark Thompson has coach Rick Stockstill looking to slide junior Alex Stuart from right guard to center. Stuart also worked at right tackle in 2008.
Stuart missed four games last season with ankle problems, which have continued to linger into this fall's practices.
Right tackle Mark Fisher was named to last season's All-Sun Belt second team, and is a member of this year's preseason first team. He's started 35 of 37 career games at right tackle.
Fisher allowed only two sacks in 2009, while grading out at better than 80 percent nine times.
Junior Mike Williams returns for his third season as the starter after leading the Raiders with 68 knockdown blocks last year.
Despite being slightly undersized for the position at 6'2" and 260 pounds, Williams has been one of the line's strongest performers since his first game.
Junior left guard Brandon McLeroy returns to add to his total of 18 starts. Five of his 12 starts in 2009 came on the right side before he settled in on the left. He earned MTSU's most improved offensive lineman award during spring practice.
The new starter will be Tennessee transfer Preston Bailey at right guard. The 6'5" sophomore, a native of Nashville, still has yet to take the field in a college game. He was a three-star recruit by Rivals when he signed with Tennessee, and the Raiders are now hoping to benefit from that potential.
Experience is in good supply off the bench, as well. Senior Chris Hawkins has started at both center and right guard during his career, and junior Colin Boss has filled in at all five line positions.
3. Troy
Like MTSU, Troy is repositioning a guard into the center spot. All-Sun Belt first-teamer Tyler Clark is headed to the middle of the line to replace his fellow all-league performer, Danny Franks.
The former walk-on has started 31 games in his career and didn't allow a sack until the 12th game of last season against Louisiana-Lafayette. His interior pass blocking skills are expected to help make quarterback Jamie Hampton's job easier as he seeks to replace record-setting Levi Brown.
Tackles James Brown and Kyle Wilborn return to their starting positions. Wilborn started 12 of 13 games as a freshman, establishing himself as a bruising run blocker. A bit of work may still be required with his pass blocking. He's currently recovering from arthroscopic knee surgery, but is expected to be back for the season opener against Bowling Green.
Brown, a massive 6'4", 346-pounder, should be a fearsome weapon as the Trojans put more emphasis on the running game. He's not an extremely nimble pass protector and has a penchant for holding penalties, but if he gets running downhill, linebackers and safeties may decide that tackling Trojan runners is someone else's job.
Senior Tyler Graves's career has taken a winding route from Florida State to Pearl River Community College to Troy. He's in line for the starting position at left guard after a difficult first start at right tackle last season against Arkansas State.
He managed to keep all-conference end Alex Carrington from recording a sack, but was called for five penalties in doing so.
Sophomore Jacob Creech appears to have inherited a clear path to right guard with Micah Grimes quitting the team. Creech is a 6'4", 281-pounder who's gotten most of his experience on special teams.
Experienced depth isn't in huge supply right now. Senior Nate Newland is set to help at both tackle positions, and junior Zach Swindall is set to help at center.
A pair of mammoth junior college transfers, Jarred Fleming (6'7", 280) and Demarkus Underwood (6'6", 315) are battling for time at tackle spots.
4. Arkansas State
Arkansas State's offensive line is easily the Sun Belt's most experienced, if not the most talented.
The Red Wolves have nine different players returning who have started at least one game, thanks to major injury-induced turnover last year. Four of their regular starters return, and all five projected starters are seniors.
Right tackle Derek Newton was a second-team All-Sun Belt performer, and is rated as one of the conference's best pro prospects. The 6'5", 313-pound senior runs well for his size and excels on both the run and pass. He's expected to be a great fit for ASU's new no-huddle offense.
Next to Newton, right guard Sifa Etu came from the junior college ranks to start 10 games last season. He was also recruited by Miami, which gives an indication of his talent level. He's a squatty bulldozer who should open some massive holes for running back Derek Lawson.
Senior Drew Hilton is a Swiss army knife of a lineman. He'd played right guard before opening last season at left tackle. This season, he'll get first look at left guard, giving coach Steve Roberts serious versatility in case the injury bug tries to bite yet again.
A battle is brewing at left tackle, where junior Delano Moore has overtaken senior Kiano Prater. The two are identical in build at 6'5" and 305 pounds and are both prone to mistakes in pass blocking. Whoever can remedy those mental mistakes quicker will earn the starting nod.
Senior center Tom Castilaw started last year's first four games before suffering a knee injury. His replacement, sophomore Eric Allen, missed most of the offseason work with a shoulder injury.
Senior Albert Louis (6'3", 303) is another potential reserve with starting experience. He started four games early last season at left guard.
In total, a line built for pounding away at the running game now must adapt to a quicker-paced offense. If they fail to do so, it could be a very long season in Jonesboro.
5. Western Kentucky
The Hilltopper offense is heading in the opposite direction as Arkansas State's. New coach Willie Taggart has his team installing a traditional two-back attack after the spread offense was unable to produce any victories.
The line paved the way for 172.8 rushing yards per game, fourth in the Sun Belt. Returning tackles Preston King and Wes Jeffries have the kind of size and strength that will help the WKU backs record a similar figure.
Both, however, have trouble with solid pass rushers, a problem put on paper by WKU's league-worst 39 sacks allowed in 2009.
Senior Mychal Patterson will return to the left guard spot. He's another solid run blocker who could also play on the right if need be.
Sophomore Seth White is expected to take over at right guard with last year's starter, Adam Smith, moving to tackle.
White has added 15 pounds to his frame since coming to Western, and he's one of the few men on this unit with a reputation as a strong pass blocker.
At center, senior Derrick Elder will become the line's signal caller after seeing time at both guard positions last year. The 6'2", 308-pounder is, like many of Western's linemen, much more respected as a run blocker than a pass blocker.
Sophomore Adam Smith was last year's starter at right guard, but now heads to the bench, where he's likely to fill in at both guard spots and threaten King at right tackle.
Sophomore Ed Hazelett is a former three-star recruit who turned down offers from the likes of Boston College, Kentucky, and Louisville because they wouldn't let him play basketball. At 6'8" and 296 pounds, he's seen as a potential tackle of the future.
If all these linemen can run block as well as advertised, Hilltopper running back Bobby Rainey should have a tremendous season.

6. Louisiana-Lafayette
Last year's ULL line allowed only 86 yards in sacks, fewest in the conference. This year's line returns only two members of that group, losing two All-Sun Belt first-teamers and another two-year starter.
Senior Ian Burks returns, but like the centers on so many Sun Belt rivals, he's trying his hand at center after 30 starts at right guard.
He did start in the middle last season against Nebraska, and despite the 55-0 scoreline, the Ragin' Cajun linemen were proud of not allowing a sack.
Right tackle Jonathan Decoster has started the last 31 games at that position, and has received some preseason All-Sun Belt mentions. He and Burks will have to lead a unit short on experience.
Senior Colin Windsor takes over at left tackle. He's played in only 19 games with one start, but compared to his competition, redshirt freshman Robert Robinson, he's a grizzled vet.
Sophomores Leonardo Bates (6'5", 320) and Jaron Odom (6'7", 340) are projected to start the season at the guard positions. Odom appeared in all 12 games with one start last season, and Bates appeared in seven games off the bench.
Junior Kyle Plouhar is the most experienced reserve, with 18 appearances in two seasons. Senior tackle Nasser Jamal is expected to contribute on the outside. Despite his four years in the program, Jamal's only made eight appearances on the field.

7. Florida International
FIU only returns one starter from a unit that allowed the second-most sacks in the Sun Belt last season. Taking those two facts together, perhaps a lack of experience could be a good thing.
Center Brad Serini is a Rimington Award watch list member for the second straight season. He's started every game since setting foot on campus back in 2007, and is arguably the best center in the Sun Belt Conference.
Senior Kevin Van Kirk was expected to take over at right guard before spraining his knee in this past Saturday's opening scrimmage. Fellow senior Cedric Mack, who started four games at the position in 2009, appears likely to retain the position.
Junior James Wiggins has the inside track at left tackle, and sophomores Dave Istanich and Rupert Bryan are battling at right tackle.
Wiggins is known as a solid pass blocker with quick feet, and may prove solid once he gets some games under his belt.
The 6'6", 300-pound Istanich got six starts last season, mostly at guard, but the coaching staff liked his massive frame at tackle. Both he and Bryan are known as highly shaky pass blockers.
Sophomore Giancarlo Revilla is expected to start at left guard after three appearances last year. A center prospect when he was recruited, he may follow the Sun Belt trend of relocating to center when Serini graduates.
Junior Chris Cawthon can help out at both guard positions, and has starting experience from the 2008 season.
8. Louisiana-Monroe
The Warhawks lost three starters and four prominent backups from last season, and with a battle going on at quarterback, poor protection will not be easy to overcome.
Last year's group allowed only 16 sacks, third-fewest in the SBC, and managed to shut the mighty Texas Longhorns out of the sack column.
The left side of the line will be anchored by last year's right side. Junior tackle Justin Roberts and sophomore guard Jonathan Gill flip sides this season.
Gill, a 6'3" 290 pounds, started all 12 games in his freshman season and recorded over 130 knockdown blocks.
The 6'4", 300-pound Roberts has started the last 22 games and recorded over 120 knockdowns last season.
Senior Andrew Stout is the most experienced of the new starters, playing in 27 games over the last three seasons. The majority of that action, however, has been on special teams.
Junior college transfer Ryan McCaul is expected to get the opening nod at center. He was an all-conference performer for Northeastern Oklahoma A&M.
The extent of right tackle Anthony Montgomery's notes in the ULM fan guide reads "Key member of the scout team." As that succinct line suggests, Montgomery has not appeared in a game after two seasons in Monroe.
The reserves will be largely new to ULM fans, as junior college transfers Jordan Karriman and Patrick Dvoracek are listed second at both guard spots and tackle positions, respectively. Four freshmen have also been seeing time in fall practice.
9. Florida Atlantic
The best offensive line in FAU history is gone. All of it. FAU's skill position players are highly concerned about the state of the inexperienced replacements.
The Owls do have one offensive linemen with starting experience. Unfortunately, that experience was as a defensive lineman. Left guard Andy Czuprynski moved from defensive tackle to offensive line due to the crippling lack of depth.
Center Jordan Sessa is one of the biggest linemen on the team, which is mildly worrisome, since he weighs in around 280 pounds. A knee injury with no timetable for his return, however, has FAU scrambling for alternatives.
Backups Jimmie Colley and Ryan Houston have also suffered injuries, and junior Mike Nweze appears the most experienced snapper left. His resume consists of a few practices.
Sessa's a mammoth compared to redshirt freshman Eric Hansen, who's got the inside track on the right guard position. Hansen, at 6'5" and 240 pounds, is smaller than some tight ends.
The Owls have been known to utilize smaller, more athletic linemen, but Hansen will certainly need to add some bulk to survive on the line.
Junior Sam McRoy looks to be the starter at left tackle. His class status would indicate some experience, but McRoy has appeared in only 10 games at various positions.
At right tackle, a spirited battle is being waged by 6'8", 300-pound junior Max Karrick and 6'5", 263-pound sophomore Joseph Bailey.
Freshman DeAndre Williams was being recruited by other Sun Belt schools, as well as Iowa State, but if there's one thing available at FAU, it's opportunity. The 6'5", 265-pounder may help out at both tackle spots.
The potential for surprises, both pleasant and unpleasant, appears to be the theme in the trenches for the Sun Belt Conference's nine teams this season.
Some talented offensive players have to be concerned about whether they'll have time and space to operate.
Scott Henry covers the MTSU Blue Raiders on his radio show 4 Quarters, airing on WMTS 88.3 FM in Murfreesboro and streaming live at wmts.org. Podcasts may be found at Starr*Rated.
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