Back from surgery, Rob Sims and Chris Spencer look to strengthen the Seahawks offensive line

RENTON — Rob Sims didn't know how serious his injury was.

It wasn't until he tried to put his carry-on baggage in the overhead compartment of the team's charter plane in Buffalo that he got his first idea of just how serious an injury he suffered in Seattle's season-opening loss to the Bills.

"I couldn't get my arm past my shoulder," Sims said.

Two days later he was diagnosed with a torn pectoral muscle that required season-ending surgery, and the year in which the Seahawks simply could not stay healthy was under way.

By November, center Chris Spencer's back was so sore that just tying his shoes was excruciating, let alone standing his ground against the carnivorous, 300-pound nose tackles that populate the NFL. Spencer didn't play at all in December, missing the Seahawks' final five games.

By the end of the season, all five men who began training camp as the first-unit offensive line were injured and unable to play.

Some teams rebuild in the offseason; the Seahawks' offensive line rehabilitated, and the left side of the line is still recovering. Tackle Walter Jones is coming back from knee surgery, guard Mike Wahle from a shoulder injury.

But Sims and Spencer are back with a new blocking scheme and a fresh opportunity to fulfill the expectations once heaped upon them.

Spencer is a former first-round pick in the final year of his contract who has had a hard time staying healthy. Sims is a former fourth-rounder who made an early impression while climbing up the depth chart in 2006, but has not distinguished himself in two years as a starter.

Their job security became a question when Seattle drafted Max Unger in the second round last month. Unger played center his final two years at Oregon, but offensive coordinator Greg Knapp was quick to say that Unger wasn't necessarily supplanting Spencer and would play guard, too.

"Spencer's still the center here," Knapp said the day after Unger was drafted. "Spencer is still going through the process of learning this offense and he's doing fine. He's done great since Day One when we got in the building."

Unger played left guard, Wahle's spot, with the second unit during the three-day minicamp for rookies last weekend.

The Seahawks are switching to a zone-blocking scheme, which in layman's terms means each lineman is assigned to block a certain spot rather than a specific defender. The shift also puts more responsibility on the center for making sure the middle linebacker is accounted for, something the quarterback does under other systems.

"A lot is going to be on the center's plate," Spencer said. "But it's going to be good for us."

Spencer is a 310-pound center who can move, and this will be his fifth season with the Seahawks. He suffered a shoulder injury that required surgery in 2007, and last year a bulging disk in his back kept him out for a good chunk of training camp. He came back, but by the end of November that bulging disk was herniated.

He's recovered now, and ready. So is Sims, who is 311 pounds but leaner and stronger than before the surgery.

Putting his carry-on bag in the overhead bin is no problem. Now, he's just got to shed the rest of the baggage the Seahawks carry from last year's injury-ravaged season.

"Last year sucked," Sims said. "All the way around. It just sucked, man. There's no other way to really describe it."

Danny O'Neil: 206-464-2364 or doneil@seattletimes.com