A black bumper sticker is plastered on linebacker LaVar Arrington's locker-room stall above a clutter of hangers, jerseys, sneakers and other Washington Redskins paraphernalia. "Walk Your Talk," the sign implores in red-and-white letters.

"It was fitting, so I put it on my locker because a lot of guys talk," Arrington said. "Hell, I've been talking. We haven't done anything, so walk your talk."

Last year, after Arrington served under his fourth defensive coordinator in four years, the linebacker posted a description of the Battle of Thermopylae -- where the Greeks made a heroic stand against the Persians in 480 B.C. -- to mark the start of a new era.

Now Arrington has yet another leader in Gregg Williams, the assistant head coach-defense who has the reputation as one of the NFL's best defensive minds. Arrington's positive attitude heading into this season has been no different than previous offseasons. However, Arrington believes that one change will allow him to realize his full potential: moving from strong-side linebacker to weak-side linebacker for the first time as a professional.

Since being selected second overall in the 2000 draft out of Penn State, Arrington has appeared in three consecutive Pro Bowls while generally playing across the offense's strong side -- wherever the tight end lines up.

Washington's new defensive coaches have played down the change -- "It's no big deal," said Dale Lindsey, the linebackers coach -- noting that Arrington has occasionally lined up on the weak side during his NFL career. However, there's a significant difference between the positions, and Arrington believes the switch maximizes his strengths and allows him to use his athleticism to roam from sideline to sideline to make plays and rush the passer.

"All the critiques and comparisons: 'Why isn't he doing the things that he did at Penn State?' I wasn't at the same position," said Arrington, who practiced yesterday after resting his sore left knee Wednesday. "Now I'm literally at the same position. I feel like I'm sitting at Penn State again for the first time in the NFL."

Playing weak-side linebacker, Arrington became one of the most dominant defensive players in college football history during his final year in 1999. Arrington earned the Chuck Bednarik Award as the nation's premier defensive player and the Dick Butkus Award as the top linebacker.

In 2000, the Redskins switched Arrington to strong-side linebacker because the team's other starting linebackers were better on the weak side. The defensive coordinators that followed didn't switch him back largely because the club didn't have a true strong-side linebacker.

Although the weak-side linebacker has less responsibility and is considered a less difficult position, Arrington underwent an adjustment period early this preseason. "The grace period is over," said Arrington, who recorded a sack against the Tampa Bay Buccaneers in the Redskins' 16-10 victory Sunday. "Halfway through preseason, I felt good."

Arrington has averaged 99 tackles and five sacks per season in his NFL career and has been one of the league's most popular players. But Arrington, whose Redskins teams are 28-36, hopes his new role will lead to his first NFL playoff appearance.

At 6 feet 3 and 253 pounds, Arrington is bigger than the typical weak-side linebacker yet possesses the requisite athleticism. The strong-side linebacker is responsible for covering the tight end and must occasionally shed blocks from fullbacks. The weak-side linebacker is often matched up against tailbacks, making it easier to break free and make tackles.

"LaVar will have a lot more one-on-ones. He'll be able to make more big plays," said middle linebacker Antonio Pierce, who has played all linebacker spots. "At Sam [strong-side linebacker], you have somebody in your face all the time."

The Redskins made the switch during the offseason after acquiring strong-side linebacker Marcus Washington from the Indianapolis Colts. "Once we had Marcus," Lindsey said, "it was a no-brainer."

Arrington's role was spelled out in an extensive discussion with Williams before Coach Joe Gibbs's first minicamp in March. Williams revealed his vision for changing a defense that finished last season ranked 25th in the 32-team league. "To his credit," Arrington said, "he's come through with everything he said."

Williams plans to sometimes use Arrington as a defensive end on third-down passing situations, a role that the linebacker groused about under defensive coordinator Marvin Lewis in 2002. Although Arrington finished with a career-high 11 sacks, tops among NFL linebackers, the part-time role strained his relationship with Lewis, who felt that the linebacker needed to improve his pass coverage. Last season under defensive coordinator George Edwards, Arrington was pleased that he rarely had to go into a three-point stance.

But Arrington hasn't expressed any qualms about being used as a down lineman in nickel packages, when the Redskins send five defensive backs onto the field. Arrington now says he shouldn't have resisted as much under Lewis, and added that the experience gave him more confidence with his hands on the ground.

Arrington is needed as a third-down defensive end partly because the Redskins don't have a pure pass rusher.

"I have an opportunity to play in my natural position and get better at playing defensive end and wherever else they play me," said Arrington, who started 16 games last season, collecting 116 tackles and forcing a career-high seven fumbles. "I feel pretty good about the situation that I'm in, and that this team is in."

When the Redskins face the Giants on Sunday, Arrington will seldom match up against Pro Bowl tight end Jeremy Shockey, whose speed and strength at 6-5 and 252 pounds makes him a tough assignment. But Arrington's competitive side causes ambivalence.

"I would love the opportunity to lock horns with him," Arrington said. "He's so dangerous and he's such a good player that we're going to have to put a concentrated effort at trying to slow him down. I love to compete, but Marcus is more than capable of holding down that area."

"I feel like I'm sitting at Penn State again," LaVar Arrington said of his move back to weak-side linebacker.