The Chargers (4-6) placed starting LT Jared Gaither (groin) on the season-ending injured-reserve list on Friday.

After being released from the Chiefs, Gaither was a late season free agent acquisition in 2011. He allowed only three pressures and zero sacks in the final five games for San Diego last season.

He was then re-signed this offseason to a four-year contract worth $24.6 million, with an $8 million signing bonus and $13.5 million guaranteed.

After being handsomely rewarded, Gaither has played in just four games this season. He suffered a “full body cramp” in the first full practice of training camp that was later described as back spasms. He missed nearly two months before playing in Week 4 against the Chiefs. He then suffered a groin injury late in the game against the Saints in Week 5.

After the Chargers bye in Week 7, Gaither returned to action in Week 8. He reinjured his groin early in the game against the Chiefs in Week 9 and hasn't played since.

LT Mike Harris (undrafted, UCLA) has started six games this season in place of Gaither and will remain the starter. Harris played well early on, but his performance has diminished in recent weeks.

San Diego will also likely be without starting LG Tyronne Green (hamstring) against the Ravens on Sunday. Green hasn't practiced this week. Utility guard Rex Hadnot is slated to start in place of Green.

C David Molk (round seven, 226th overall) is the only remaining backup offensive lineman. Molk entered the game last week at right ruard when Luis Vasquez missed a few snaps with an ankle injury. Vasquez has practiced throughout the week and is expected to start.

Coach Norv Turner indicated that OT Kevin Haslam will be activated off the practice squad to replace Gaither’s spot on the 53-man roster. Haslam played five games for the Jaguars in 2010. He has been working exclusively at the tackle position.

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