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Max Unger is tall and wears his weight high. He was a center at Oregon, but Oregon runs an unorthodox offense. Unger does not have the ideal build of a center and Seattle has converted him to guard. But did Seattle select Unger to play guard, or is he a guard today out of deference for Chris Spencer?

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Is it any wonder Tim Ruskell values center so highly?

Chris Spencer: Spencer is supposed to be that rare blend of build and athleticism that can play in any system, and maybe he can. His footwork and overall technique are a work in progress, but Spencer has shown progress. He improves every season. That is significant, because at 27 Spencer is not in the midst of his prime, but really just entering it. I do not know the specifics of it, I would guess it is a combination of knowledge, upper body strength and finding the right fit, but center peaks late. Waaay late.

The player every Seahawks fan wants Spencer to be, Robbie Tobeck, was starting at left guard for the Atlanta Falcons when he turned 27.He was blocking for the much sacked Chris Chandler and Billy Joe Toliver, both were sacked on greater than 10% of all pass plays, and the then unknown Jamal Anderson. Anderson averaged 3.5 yards per carry that year.

Tobeck signed a free agent contract with Seattle in 2000. He was 30. The contract was for five-years, $6.8 million. As a six-year veteran, his pay was a little more than double the veteran minimum. Tobeck was not a highly sought free agent.

Nor is he a very fair comparison for Spencer or a standard for what Spencer should become, but he is a familiar example of a retread offensive line talent that seemed to peak late. Ruskell drafted Spencer while Tobeck was still starting. Spencer was not a longtime starter at Mississippi and was a bit unpolished entering the NFL. Ruskell must have known that though Spencer was talented enough to start in a pinch, his real value was locked in his potential.

So if Spencer is improving and entering the period we would assume to be his prime, why does it seem certain the Seahawks will not retain him?

Max Unger: Seattle avoided the inherent controversy created by drafting a center in the second round of the 2009 draft by quickly converting that center to a guard. It wasn't unthinkable that Unger could be a guard, but it wasn't exactly conventional wisdom either. Unger himself has said he is a center and wants to play center. Maybe five years from now that will be forgotten, but it seems important today.

Unger is playing right guard but it would not be a radical or retarding decision to switch him back to center following the 2009 season. He has extensive college experience at center and while 2009 may forever be a year of lost development for Unger the center, I assume he would pick it back up if needed and already be more developed at the position than he is guard.

There is something odd afoot and it leaves me unsure of Seattle's plans.

Whatever the plan, and maybe the plan is only to have options, Seattle is stacked at center. Spencer is quietly becoming a very good center, but his contract ends at the end of the season. An uncapped season would make him a restricted free agent, and I am sure Ruskell would take the chance to save money, but does he return Seattle's center of the future or a one year stopgap blocking a large investment?

Spencer has the center's build. He is between 6'2" and 6'3", carries his 309 throughout his body and over a strong lower half. He is an ideal matchup against the suddenly pervasive 3-4 nose tackle.

It was when watching Unger get blocked back against college level nose tackles that I first began seeing him as a guard. Unger is 6'5", and carries his weight on his shoulders and through his midsection. He is a technical blocker that doesn't overpower and may never matchup well against ever-larger 3-4 nose tackles. As a pass blocker, he is best using technique to ward off and slow rushers, using his reach and slide step to keep the defender ahead of him. He is weak against the bull rush and the bull rush is the primary weapon for most nose tackles.

Steve Vallos: When Spencer missed the first two games of the season, Vallos started at center ahead of Unger. Vallos started at left guard in week six, so Vallos did not start ahead of Unger because the team did not trust Vallos to play guard.

Vallos was okay at center. As I would expect, he was where he was supposed to be, but unlike I would expect, he wasn't there getting his face punched off. Zone blocking schemes are designed to protect players like Vallos, and though he can look almost puny at times, smaller players than Vallos have succeeded in the system. It seems odd to say it now, and I won't hesitate to say it might be premature (Vallos started against the Rams and 49ers) but Vallos looks like decent, extremely cheap center depth, and there's nothing wrong with that.

Seattle might be superabundant at center or it might be months away from looking for a new one. Spencer is a great physical talent and he could be a great zone blocking center, but his standing within the organization has always seemed shaky and his rookie contract is coming to an end. Unger could be his successor or already permanently converted to guard. That would make me happy, but maybe not Unger. The bare facts are that Seattle has invested tremendous resources into the position and acquired great talent and depth, but it's anyone's guess who plays center for the Seahawks in 2010.