Veteran Anthony Herrera will start in place of John Sullivan at center for the Vikings in tonight's preseason game against Seattle. Sullivan isn't in uniform for the game and has yet to play in an exhibition game after suffering a calf injury early in camp.

Herrera played center last Sunday for a series at San Francisco for the first time since 2005 and impressed coaches with his performance. Rookie Chris DeGeare will get the start at Herrera's normal right guard position.

This move means that Jon Cooper might not be assured of making the roster. Sullivan returned to practice last week but did not take part in all drills. There has to be real concern now if Sullivan will be ready for the Sept. 9 regular-season opener at New Orleans.

Wide receiver Percy Harvin is active but Greg Lewis will start in his place. Harvin has not practiced since Aug. 19 when he collapsed on the field at Winter Park after having an issue with migraines.

Rookie Chris Cook, meanwhile, will get the start at right cornerback, meaning three different players have started in that spot in three preseason games. Cook could win this job.

Defensive tackle Jimmy Kennedy, who suffered an undisclosed injury last Sunday, is the only player declared inactive by the Vikings.

Seattle's inactives include: cornerback Josh Pinkard; guard Ben Hamilton; linebackers Leroy Hill and David Hawthorne; guard Chester Pitts; tackles Ray Willis and Russell Okung; tight end Chris Baker; defensive tackle Kentwan Balmer; and defensive end Nick Reed.

The Seahawks starter changes are Leon Washington for Julius Jones at running back and Mike Gibson for Hamilton at left guard.