RENTON — Adjusting to injuries on the offensive line is nothing new for the Seattle Seahawks.

Feeling confident the next player up is ready to do his job, however, is different.

By overhauling the roster over the past two seasons, Seahawks head coach Pete Carroll and general manager John Schneider believe they have created a deeper team, top to bottom. Over the last four games, they’ll find out just how deep they are on the offensive line.

Left tackle Russell Okung was placed on injured reserve Tuesday because of a torn pectoral muscle he sustained in last Thursday’s victory over the Eagles. Seattle has now lost three of its five starting linemen for the season following last month’s injuries to right guard John Moffitt and right tackle James Carpenter. But unlike the past two seasons when Seattle has often had to sign players, then rush them onto the field — who can forget Tyler “Troy” Polumbus starting at left tackle when Carroll didn’t even know the new tackle’s first name — this year’s Seahawks have players on the bench they believe can do the job.

Paul McQuistan, who has started six games this season at both guard spots, will move to left tackle to take Okung’s spot. That leaves a vacancy at right guard, where McQuistan was starting for Moffitt. That role will now be filled by Lemuel Jeanpierre, who has started one game this season at center.

“We pretty much have to head in that direction,” Carroll said. “Hopefully it will work out fine. Paul’s not unfamiliar with playing tackle, so that helps. The fact that these guys have been with us and we don’t have to go outside of the organization and the system to get guys is really very fortunate, and it does speak to the depth that we started camp with.”

McQuistan will have a tough task moving to left tackle, arguably the second most difficult position on an offense behind the quarterback. But he has played a bit at that position, most recently in 2008 while in Oakland. He also started at right tackle in 2007.

“Different stance, that’s about it,” McQuistan said. “The speed of the guys is a little different. … It’s more of a finesse spot than guard. It’ll be a good challenge over there.”

McQuistan, who was signed in the offseason, played in this system under Tom Cable in Oakland. Cable is now the Seahawks’ offensive line coach. Jeanpierre, meanwhile, is well versed in the Seahawks offense despite limited game experience. Last year he was on Seattle’s practice squad as an undrafted rookie, and he made the 53-man roster this year as a backup guard and center.

Now Jeanpierre plans to show he can help Seattle’s line not miss a beat despite another injury. Seattle has rushed for 100 or more yards in each of the past five games, something it hasn’t done since 2005, and injuries or not, the line doesn’t plan on taking a step back.

“I’m happy they have faith in me to go in there and step in,” Jeanpierre said. “I’ve got to work my butt off and prove them right.”

As for playing guard and center, Jeanpierre said he doesn’t see much difference in the two: “It’s two big guys hitting each other, that’s how I see it. … Once that ball is snapped, you’re making contact.”

With McQuistan moving to tackle and Jeanpierre, the backup center, moving into the starting lineup, the Seahawks signed guard Mike Gibson on Tuesday. Gibson, who can play guard and center, spent last season with the Seahawks, starting eight games at both guard positions. He was released following training camp in September.

Herald Writer John Boyle: jboyle@heraldnet.com. For more Seahawks coverage, check out the Seahawks blog at heraldnet.com/seahawksblog