LT Mike Harris was one of many Chargers offensive linemen hurt Sunday vs. the Bengals. (US Presswire)

The Chargers' already shaky O-line was decimated against the Bengals on Sunday. RT Jeromey Clary (knee), LG Tyronne Green (hamstring), LT Mike Harris (ankle) and backup center turned backup utility guard David Molk (thumb) all suffered or re-aggravated injuries and are not expected to play against the Steelers (7-5) in Pittsburgh on Sunday.

On Tuesday, to make room for two more offensive linemen, San Diego (4-8) placed WR Seyi Ajirotutu (hand) and Molk (thumb) on the reserved-injured list. (Ajirotutu was also injured against the Bengals.) That cleared the way for C Colin Baxter and G-T Stephen Schilling to be re-signed.

Baxter, 6-3, 310, originally joined the Bolts in 2011 as an undrafted free agent. He was released from the Chargers at the conclusion of last year’s camp. He then signed with the Jets where he played in three games, but he was released due to poor play. He rejoined the Chargers and performed better in five games. Baxter was released again at the end of training camp this year on Aug. 31.

Schilling, 6-5, 308, was a sixth-round draft pick by the Bolts in 2011. He played in nine games and started one game each at right and left guard as a rookie. Schilling was also released on Aug. 31.

Baxter will wear No. 64 and Schilling will wear No. 72.

On Wednesday, OLB Antwan Barnes (hamstring) was placed on the reserve-injured list and G-T Reggie Wells was re-signed. 

Barnes played in 11 of 12 games this season. He had three sacks among six total tackles, including two sacks against the Ravens in Week 12 when he suffered his injury.

Wells, 6-4, 318, was originally a sixth-round selection by Arizona. He spent the first seven years of his career with the Cardinals. In 2010 he was traded to the Eagles, and he played for the Panthers in 2011. He has appeared in 117 games and made 91 career starts.

Wells went to training camp with the Packers in 2012 before he signed with the Chargers. He spent 11 days in San Diego (Sept. 11-22) but didn't appear in a game, and he hasn't played this season. Wells was released in September over LT Mike Harris (undrafted, UCLA). He will wear No 74.

Harris did not practice on Wednesday, but coach Norv Turner said he is improving and has the greatest chance of playing of the injured members of the O-line.

Going with the assumption that Harris won't play, here is a projected starting O-line for Sunday: RT Reggie Wells, RG Louis Vasquez, C Nick Hardwick, LG Rex Hadnot and LT Kevin Haslam. The likely backups are Schilling for the guards and tackles and Baxter at center.

Haslam was promoted off the practice squad on November 24th and saw his first action with the Chargers last Sunday, and that was also his initiation for working with QB Philip Rivers. “I went out there and he called a play,” Haslam said. “That was my first time.”

The Steelers top-rated defense (259.8 yards per game) only has 25 sacks (ranked 20th) this season, but this will be an opportunity for them to increase that total.

“If I was up front, I would be licking my chops,” ILB Larry Foote said. “I’m quite sure (OLBs) James Harrison and [LaMarr] Woodley are trying to get back healthy to play.”

Harrison was slowed by a knee injury at the start of the season, but he has come on strong and has a sack in each of the last three games. Woodley (ankle) did not practice on Wednesday and was inactive last week against the Ravens. He has four sacks this season.

Turner is relieved to have replacements that are at least familiar with the system. “It is the only way you can go,” Turner said. “There are not a lot of guys out there right now and there are teams looking for guys. Having guys who are familiar, who know our guys and can line up and execute assignments, understand the assignments in a four-day period, which is probably the best you can do.”

Hardwick, the veteran leader of the O-line, said the biggest challenge this week is communication. “Make sure everyone is in-sync,” Hardwick said. “The more we can talk about our blocks and talk about what we are seeing, the more effective we will be on Sunday. It’s just a collective effort from all of us. Everybody has to talk to the man next to him and talk collectively about what we are seeing, how it’s going to unfold and where we expect our bodies to be on every particular play.”

Not only will newly formed O-line be concerned about keeping Rivers upright, but drives could stall because the lack of continuity could lead to penalties such as false starts and delay of games. “We can get up to speed on that and we should not have any issues,” Hardwick said.

San Diego is realistically out of playoff contention. This has led many to suggest that Rivers should sit because his health is more important to the long-term future of the franchise than a win.

Rivers has not missed a game since he became the starter in 2006 and has no plans of ending that streak. “They’re kicking it off on Sunday,” Rivers said. “Last I heard, they are playing and it counts.”

Injury Report: Did not participate: ILB Donald Butler (groin), RT Jeromey Clary (knee), LG Tyronne Green (hamstring), LT Mike Harris (ankle), WR Eddie Royal (hamstring) and S Darrell Stuckey (hamstring). Full participation: OLB Jarrett Johnson (back), S Corey Lynch (quad) and TE Dante Rosario (hamstring). Clary, Harris, Johnson and Lynch were new additions to the list following Sunday’s game.

What’s next: The Chargers will practice in pads on Thursday

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