Hawks’ offensive line takes step forward, two back

RENTON, Wash. – The progress of the Seattle Seahawks’ offensive line is running up against setbacks in the training room.

Rookie right tackle James Carpenter, the team’s first-round draft pick, left practice Wednesday with a knee injury that will require further evaluation. He was undergoing a magnetic-resonance image (MRI) test, results of which won’t be available until today.

It’s the second knee injury suffered in four days on Seattle’s offensive line. Right guard John Moffitt suffered a season-ending knee injury in the first quarter of Sunday’s game against Baltimore. Carpenter and Moffitt were the first two players Seattle chose in the draft last April, choosing Carpenter No. 25 overall out of Alabama and Moffitt in the third round from Wisconsin.

Seattle picked them to form the right side of the offensive line for the foreseeable future. The pair had started every game this season for Seattle. Carpenter began the season at left guard, filling in for Robert Gallery, before moving to right tackle, the position he was picked to play.

The Seahawks offensive line was the biggest concern for the team entering the season and through seven games, Seattle had allowed the most sacks in the league and gained the second-fewest rushing yards. That had changed over the past two weeks, though. Seattle had allowed a total of two sacks in games against Dallas and Baltimore, and running back Marshawn Lynch ran for more than 100 yards in back-to-back games for his first time as a Seahawk.

Breno Giacomini is the backup at right tackle.

McQuistan to start

Paul McQuistan will start at right guard for the Seahawks this weekend against the St. Louis Rams in place of Moffitt. The 6-foot-6, 315-pound McQuistan started three games for Seattle earlier this season at left guard when Gallery was out with a groin injury.

“We feel comfortable with him playing,” coach Pete Carroll said of McQuistan, a six-year veteran. “He’s well-versed (in our system) and he’s played all of the spots for us.”

Lemuel Jeanpierre replaced Moffitt on Sunday and will serve as a backup guard and center.

Notes

Tarvaris Jackson only threw one pass in Wednesday morning’s walk-through and was limited in the afternoon practice because of a strained pectoral muscle. The team is taking it day by day with the quarterback. “Unfortunately, he just can’t practice very much,” Carroll said, “and when he does, he’s holding back.” It is still uncertain whether the injury will require offseason surgery. … Kam Chancellor was a full participant in practice after suffering a concussion last week. against Baltimore, and Carroll said he’s “confident” the safety will be able to play Sunday against the Rams. Receivers Sidney Rice and Doug Baldwin, and linebacker David Vobora are also recovering from concussions and all have “a good chance” of playing Sunday, according to the coach. … Tight end Cameron Morrah (toe/knee) is expected to be available after missing the past two games.