KNOXVILLE -- Gary Coggin knew something had changed.

When Marcus Jackson returned from his visit to the University of Tennessee in November, the Vero Beach (Fla.) High School football coach noticed a difference in his typically quiet offensive guard.

"He came back just lit up like a Christmas tree and just liked everything about [it]," Coggin said earlier this week.

The 6-foot-2, 315-pound Jackson knew after his visit for the 52-14 win over Ole Miss that he wanted to be a Volunteer, and he announced his pledge publicly Wednesday night at the Under Armour All-American game in St. Petersburg, Fla.

"I knew when I went on my visit I was going to go there," said Jackson, who's rated a three-star prospect by Rivals.com.

"I knew I wanted to be a part of it. I feel like it's a great opportunity to be a part of. The left guard spot is open, and hopefully I can go in there and compete for it and be part of a championship O-line."

Jackson joins UT's nucleus of young offensive linemen next week when he enrolls in classes Wednesday. He arrived home from the Under Armour game early Thursday afternoon and headed to Knoxville on Friday. He'll participate in offseason workouts and spring practice.

"That's huge because he's going to have the opportunity to get into the mix of it as far as how the workouts go, learn the system, learn the terminology," said Coggin, a former Vols walk-on (1973-76).

"He's very competitive. If he has the opportunity [to play], he'll take full advantage. I see greatness in him, and I know that he's got great work ethic and great determination. If things fall in place for him, he can be special."

In their loss to North Carolina in the Music City Bowl, the Vols started three true freshmen in the line, and starting guard Jarrod Shaw is the only offensive lineman they lose heading into next season.

"Watching [Jackson] grow up -- and I've had him since he was a ninth-grader -- he's always been a pretty big kid," Coggin said. "But I've seen him develop his maturity, his strength, his confidence, and he's got a passion for it.

"It's not just get on a block; it's finish a block. He takes a lot of pride in being the best that he can be, so I think he's a great fit for the Vols."

Bullard coming home

Offensive lineman Alex Bullard, a former four-star prospect who signed with Notre Dame out of Brentwood Academy in 2008, announced on his Facebook page Thursday night that he was transferring to UT.

The 6-foot-3, 295-pound Bullard plans to walk on and appeal for a hardship waiver that would allow him to be eligible to play in 2011. His father died last spring.

Bullard redshirted his freshman year and appeared in three games this season for the Irish.

Prep star watching

The U.S. Army All-American Bowl is today at 1 p.m. and can be seen in the Chattanooga area on WRCB-TV.

DeAnthony Arnett, a four-star receiver from Saginaw, Mich., is the only UT commitment playing in the game. The 6-0, 167-pound Arnett will wear No. 1 for the West team.

Nashville offensive tackle Antonio Richardson, who began the season playing at Ensworth before transferring to Pearl-Cohn, also is in the game. It will be the first action since the midseason move for the 6-6, 310-pound four-star prospect, one of the Vols' highest remaining priority recruits.

Public commitments to UT during today's game aren't likely, but next weekend will start a stretch of three important weekends of official visits leading up to national signing day on Feb. 2.

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