Posted by ESPN.com's Mike Sando
A good veteran center can ease the mind of any NFL quarterback by reading defenses and adjusting blocking schemes. As the Colts deal with Jeff Saturday's injury, three of the four NFC West teams also face the possibility of life without an established starting center.
Arizona: A knee injury will likely sideline starter Al Johnson into the regular season. Johnson, 29, has 45 starts over the last four seasons. His replacement, 24-year-old Lyle Sendlein, has two starts, both last season. A sore knee has slowed Sendlein recently, leaving Pat Ross to man the position.
St. Louis: A hand injury has sidelined projected starter Brett Romberg recently. Romberg, 28, has 12 starts over the last two seasons. His replacement, 26-year-old Nick Leckey, might represent an upgrade. Leckey has 22 starts over the last four seasons. He might keep the job. Guard Richie Incognito has also worked at center this summer.
Seattle: A back injury sidelined incumbent starter Chris Spencer until this week. Spencer, 26, was a first-round draft choice in 2005. He has started 29 games over the last two seasons. Replacement Steve Vallos, 24, has never started a regular-season game. Vallos has played better than expected this summer, easing concerns.
The 49ers have no such issues. Eric Heitmann has brought stability to the position. The Cardinals should be able to weather Johnson's injury if Sendlein is available. Going with Ross would present more challenges. I was watching the Cardinals-Raiders game Saturday night when Ross suddenly went flying backward. Big No. 90 for the Raiders, Terdell Sands, simply overpowered him.