NAPA, Calif. -- When the team bus rolled into the Oakland Raiders' training camp on Tuesday, there was a bit of a surprise when the first person walked off.
There was five-time Pro Bowler Richard Seymour coming off a bus filled almost entirely with rookies and other inexperienced players ready to report to his first training camp with the Raiders.
While some veterans slapped with the franchise tag choose to miss some of training camp before signing their tender, Seymour ended any doubt about a holdout more than a month ago when he signed his for $12.398 million.
"Camp is the foundation that you build your success on for the season," he said. "During the season, you're spending so much time with game plans and focusing in on your opponents that you really don't have the time to work on a lot of individual things. This is my time where I really get into me and focus in on the things I need to do to make myself a better player. Come in and knock some of the rust off and be ready to go."
The Raiders acquired Seymour just before the start of last season by sending a 2011 first-round pick to New England. Seymour made an impressive debut just days after arriving in Oakland, recording two sacks in a season-opening loss to San Diego. But Seymour had only two more sacks in the final 15 games and was unable to solve the Raiders' run defense woes.
The Raiders finished the season 5-11, their NFL-worst seventh straight season with at least 11 losses. Oakland finished 29th in run defense at 155.5 yards per game.
Fixing the run defense has been one of the key tasks this offseason. Oakland used its first two draft picks on middle linebacker Rolando McClain and defensive lineman Lamarr Houston. They also signed two-time Pro Bowler John Henderson in June to bolster the middle of the line.
"I love stopping the run," said Henderson, who joined the team after offseason workouts. "That's my thing. I like to sack the quarterback too but I always like stopping the run."
The only Raiders player who remains unsigned is McClain, the eighth overall pick. Oakland has signed its other eight draft picks and hopes to have McClain under contract before practice begins Thursday.
The defensive additions from last year are notable, but the biggest change for the Raiders is at quarterback, where JaMarcus Russell has been released and Jason Campbell is expected to take over as starter.
Russell entered camp a year ago solidly entrenched as the starter after a promising finish to the 2008 season. Russell was fined upon his arrival for being overweight, a sign of things to come.
He struggled mightily in camp and when the season started before finally losing his job to Bruce Gradkowski midway through the campaign. He completed 48.8 percent of his passes, with three touchdowns, 11 interceptions and a 50.0 passer rating that was the lowest in 11 years. He was eventually released on May 6, shortly after the team's mandatory minicamp.
Campbell started 52 games for Washington since being a first-round pick in 2005. He has thrown for 55 touchdowns, 38 interceptions and has a passer rating of 82.3 in his career.
He is coming off his best season, completing 64.5 percent of his passes with 20 touchdowns, 15 interceptions and a passer rating of 86.4. But the Redskins went 4-12 last season.
The Raiders acquired Campbell during the draft for a 2012 fourth-round draft pick.
The Raiders announced Tuesday that they had hired former linebacker Greg Biekert as a defensive assistant weeks ago. ... The team will hold meetings all day Wednesday before practice starts Thursday. ... Gradkowski, sidelined all offseason with a torn pectoral muscle, has been throwing to receivers the past few weeks.