Three things: Seahawks-Chargers

Three things to watch for in the Seattle Seahawks' preseason opener against the San Diego Chargers on Thursday night. Kickoff is set for 8 p.m. ET on ESPN.

The quarterback rotation: Tarvaris Jackson will start and Josh Portis will finish. What happens in between interests me as much. No. 2 quarterback Charlie Whitehurst will stare down his former team and hardening perceptions of him as a career backup. Coach Pete Carroll professes to be all about competition, but he was all about installing Jackson as the starter before Jackson took even one snap in practice. That made sense on one level. Jackson has played in new coordinator Darrell Bevell's offense, and Jackson could use the vote of confidence after some tough seasons in Minnesota. But what about Whitehurst? Sure, Carroll said Whitehurst would compete for the job upon learning the offense, but that sounded charitable. Besides, Whitehurst has ranked third on the list of most impressive quarterbacks in Seahawks camp. Let's see how he runs the offense and whether he can throw shorter passes with greater accuracy, a necessity in the Seahawks' system.

New toys on offense: Seattle has a few of them. Receiver Sidney Rice played with Jackson in this very offense. He should have a leg up on teammates. Tight end Zach Miller, another high-priced addition in free agency, is making his Seattle debut. The other big-name addition this offseason will not play a snap. Tom Cable, hired as assistant head coach/offensive line, expects to see a more physical ground game. Right tackle James Carpenter, a first-round choice, has dominated at times during one-on-one drills. His conditioning has appeared a little shaky. How will he fare getting extended snaps?

Youth movement on defense: The Seahawks have gotten younger at linebacker and safety in particular. They also have some tall, young press cornerbacks. Second-year strong safety Kam Chancellor started strong in camp and can use the exhibition season to prove he's ready to become a full-time starter. I'm also interested in seeing how rookie safety Mark LeGree performs on passing downs in conjunction with free safety Earl Thomas. Thomas has the athletic ability to play corner against slot receivers, with LeGree taking over at free safety in those situations. LeGree was a ball-hawk in college. Will that carry over? At linebacker, the post-Lofa Tatupu era gets under way. K.J. Wright and Malcolm Smith are two rookie linebackers to watch.