Packers position preview: Offensive line

GREEN BAY, Wis. -- Between now and the Green Bay Packers' first training camp practice on July 26, we will break down each position group.

Next up is the offensive line.

Returning players: David Bakhtiari, Bryan Bulaga, JC Tretter, T.J. Lang, Josh Sitton, Don Barclay, Derek Sherrod, Lane Taylor, Aaron Adams, Andrew Tiller, Garth Gerhart.

Gone from last season: Evan Dietrich-Smith, Marshall Newhouse, Greg Van Roten.

New this season: Corey Linsley (fifth-round pick), Jeremy Vujnovich (street free agent), Jordan McCray (undrafted rookie), John Fullington (undrafted rookie).

Position coach: James Campen (eighth season, previously was assistant offensive line coach from 2004-06).

Biggest issue: For the fourth straight season, there will be a new starting center. Tretter is the favorite for the job, but the fact remains that he has never played in an NFL game – not even a preseason game. And he's never played center. Other than that, what's to worry about? Nevertheless, the Packers are high on the second-year player who spent the entire offseason working with the No. 1 offensive line. Tretter did not play at all last season after he broke his ankle during his first OTA practice as a rookie.

Player to watch: Bakhtiari had what Campen described as "a very good season for a rookie" last year when he stepped in as the starting left tackle after Bulaga blew out his knee during the Family Night scrimmage and was lost for the season. Now, as Campen said, "we expect him to make that next step and have a very good season." The former fourth-round pick played well enough as a rookie, despite allowing 10 sacks (including playoffs), according to ProFootballFocus.com, that Campen and coach Mike McCarthy decided to leave him at left tackle and move Bulaga back to the right side. Bakhtiari added about 10 pounds this offseason in an effort to improve his run blocking and better handle pass-rusher's bull-rush moves.

Medical report: Bulaga was cleared to return to practice at the start of the offseason program and made it through the OTAs and minicamp wearing a large brace on his reconstructed left knee. Meanwhile, Sherrod went through the complete offseason program for the first time in his four-year NFL career after breaking his leg late in his rookie season of 2011. Sherrod worked exclusively as Bakhtiari's backup at left tackle this offseason.

Help wanted: If Tretter does not play well enough to win the starting job, the Packers could go with rookie fifth-round pick Corey Linsley. Unlike Tretter, who played tackle in college at Cornell, Linsley is a center by trade. He started 26 straight games at center in his last two seasons at Ohio State.

Quotable: "I think I've had five centers now," Sitton said. "So it's tough because you learn one guy and you get used to doing drills next to one guy and you just jell and you know exactly where their foot's going to be and you've going to be right next to each other. Dietrich was a hell of a player, there was no doubt about it. I really enjoyed playing next to him. But that's what we do. I've played next to, I don't know, 12 tackles since I've been here, so I'm definitely used to playing next to different players. It gives T.J. and I a little bit of a challenge to get him up to speed. It makes it interesting. It's fun teaching him and bringing him along."

Previous installments

Monday: Quarterbacks

Tuesday: Running backs

Wednesday: Receivers

Thursday: Tight ends