The Chargers returned to practice on Wednesday after an off day. RB Ryan Mathews (broken right clavicle) participated in individual drills without contact for his second straight practice.

Coach Norv Turner, however, indicated Mathews will not play against the Raiders in the season opener on Monday.

“Mathews is a big part of what we do,” Turner said in regards to Mathews missing the Raiders game. “When starting this thing, talking about it in April and May, we prepared to have a situation where we didn’t have all of our guys. I like our backs.”

Playbook not limited by Harris: LT Michael Harris (undrafted, UCLA) will start on Monday in place of LT Jared Gaither (back spasms). TE Randy McMichael helped Harris throughout the preseason by chipping opposing pass rushers. Turner and QB Philip Rivers said using McMichael in that role will not limit the offensive play book.

“We have always used our backs to chip and aid in protection,” Rivers said. “It’s not a sign of a weakness from our standpoint. It may be a sign of them having a great pass rusher. It may just be an ability to hold the ball another count to get somebody running open down the field.”

Rivers also reiterated his confidence in Harris. “The [O-line] group that will be out there on Monday night is the group that we have been practicing with for a month. We will be a confident bunch.”

 Gates says he’s healthy: TE Antonio Gates is excited to start the season healthy. “Since ’07, I have not felt this good,” Gates said. “I am still 10 years in the league, so it’s not like I am pain free, but as far as the foot (plantar fascia) is concerned it’s the best I have felt in three years.”

 Brown designated to return: WR Vincent Brown was placed on the Reserved/Injured list on Tuesday.  Brown will be eligible to return later in the season because a new rule allows each team to place one player with a “major injury,” on the “Designated to Return” list. A “major injury” is defined as any injury rendering a player unable to practice or play football for at least six weeks from the date of the injury. Brown broke his ankle on August 18th in the second preseason game against the Cowboys and will be out at least eight weeks.

Haslam to practice squad: OT Kevin Haslam (undrafted in 2010, Rutgers) was signed to the practice squad on Tuesday. Haslam played in five games for the Jaguars as a rookie. He was released from the Raiders last Friday. The Chargers practice squad is now full at eight players.

Injury updates: LT Jared Gaithe r (back spasms) did not practice or workout on the side. DT Antonio Garay (left foot) returned to practice.

 Gaither has not practiced since the first day of training camp. He has repeatedly said he will not return until he’s 100 percent healthy. Turner believes Gaither can return sooner. “A lot of people are asking him questions,” Turner said of Gaither. “He might get a little defensive. He’s making progress. When he can go play I think he’ll return.”

What’s next: The Chargers will conduct their first official practice of the regular season on Thursday afternoon. After practice, an official injury report will be released.

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