KNOXVILLE -- With Tennessee just five days from the start of spring football practice, the Times Free Press is taking a position-by-position look at the Volunteers as they return to the practice field to continue preparations for the 2015 season, Butch Jones's third as coach. The series finishes up its preview of the offense with today's look at the offensive line before turning to the defense on Friday.
> Marcus Jackson (R-Sr.): After taking a voluntary redshirt in 2013, Jackson started 12 games at left guard in 2014, only missing the Alabama game due to an injury.
> Kyler Kerbyson (R-Sr.): In his first year as a starter, Kerbyson, who continues to work at tackle, was a versatile and valuable piece, starting every game at three different positions -- left tackle (10 games), right tackle (two) and left guard (1) -- and playing everywhere but center over the course of the season.
> Mack Crowder: (R-Sr.): Tennessee's offensive line was better at the end of the 2014 season, but it struggled in the two games Crowder missed due to injury. Though undersized, Crowder's value as an anchor for the line showed when the Vols were without him against Missouri and Vanderbilt.
> Jashon Robertson (So.): The former three-star recruit went from a defensive tackle at the start of the preseason to starting right guard and became an All-SEC freshman team selection after starting all 13 games. Now Robertson will actually have an offseason to get stronger. His future looks bright.
> Coleman Thomas (So.): It was a brutal introduction to college football at times for Thomas, the high school center who often struggled while playing right tackle in five games as a freshman. An ankle injury cost him two games, and he spent time at both center and tackle late last season. Thomas could push Crowder at center this offseason.
> Dylan Wiesman (Jr.): When Crowder was out, Wiesman slid into the starting center spot for two games and earned some valuable experience. He spent his freshman season working at guard, so he could give Tennessee interior depth.
> Brett Kendrick: (R-So.): After taking a redshirt year, Kendrick started games against Arkansas State and Alabama at left tackle and seemed to do pretty well. He'll be in the mix there again this offseason.
> Austin Sanders (R-So.): The former Bradley Central High School standout saw his most significant action in the second half of Tennessee's loss at Ole Miss. Sanders played left guard after Jackson went down with an injury. He missed time late in the season with an ankle injury before seeing action in the bowl game.
> Dontavius Blair (R-Jr.): The touted junior college transfer tackle Tennessee beat out Auburn and Texas A&M to land was viewed as an immediate-impact player when he arrived, but he spent last season redshirting.
> Ray Raulerson (R-Fr.): Raulerson worked at center while taking a needed redshirt season to add strength and weight to his 6-foot-5 frame.
> What a story Jacob Gilliam was for the Vols last season. The fifth-year walk-on finally earned a starting spot at left tackle and a scholarship, only to tear an ACL in the third quarter of the season opener. It could not deter him, though. Gilliam came back 55 days later, started the last six games of the season and played the TaxSlayer Bowl with a broken hand for good measure.
> Marques Pair, who appeared in just 10 career games as a backup, was a fifth-year senior in 2014.
> Jack Jones and Chance Hall enrolled in January. Both can play either tackle or guard. Jones may be more ready to play after Hall missed his senior season with an Achilles' tendon injury that may limit him this month.
> A trio headlined by Drew Richmond, the five-star tackle Tennessee swiped late from Ole Miss; Venzell Boulware, the four-star guard the Vols held off Ohio State to keep; and Zach Stewart, the local player with the disposition every offensive line coach wants.
DID YOU KNOW?
The 43 sacks Tennessee allowed last season were the most by an SEC team since Arkansas surrendered 42 in 2008 and the Vols gave up 41 in 2010. What's encouraging for Tennessee, though, is how those totals improved the following season. The Razorbacks allowed just 25 sacks in one more game in 2009, and Tennessee surrendered 18 sacks in one less game in 2011.
How much difference can a year really make? Tennessee entered last season with six combined career starts on its offensive line, by far the lowest in the SEC. The inexperience, along with a lineup that included two freshmen when the struggles were the most apparent, often showed in what was the team's biggest liability in 2014.
Throughout the struggles and all the injuries that made offensive line coach Don Mahoney's job harder, the hope for Tennessee was that all the negatives would pay off in the future, and that future is now, as the Vols enter the 2015 season with six returning players who combine for 64 career starts.
As previously mentioned, Tennessee gave up 41 sacks with an inexperienced line in 2010 and improved that number the following season. That line included four future NFL players, though, something this group likely won't be able to say. The pieces look to be in place everywhere else on the offense, and the line again will be the key to the unit's overall success.
ONE TO WATCH
Dontavius Blair was not ready to help Tennessee last season. Will the year he spent in the weight room adding strength and working on his technique help the junior college transfer give the Vols much needed help at tackle in 2015? Blair will get a chance to prove if he can play or not this spring.
Perhaps the biggest area where the Vols' line struggled in 2014 was at tackle. Tennessee was forced to play a combination of a former walk-on with one good ACL (Gilliam), a player better suited at guard (Kerbyson) and a freshman who played center in high school (Thomas) at the position. Speedy edge rushers often feasted on the group.
At 6-foot-8 and 300 pounds, Blair certainly passes the eye test. He faced some criticism for not being able to contribute right away, but there were other JuCo tackles rated higher than him that also redshirted or played sparingly in 2014. Blair's coaches were encouraged by the improvement he showed while redshirting, but spring practice will provide him the truest progress report.