Washington Redskins safety Clarence Vaughn will have arthroscopic surgery on his left knee Monday to determine the extent of the injury to his anterior cruciate ligament.

Vaughn was injured a month ago when a receiver fell on his leg during a practice. At the time, the Redskins hoped that there was no serious damage and that he would be able to rehabilitate the knee well enough to play again.

But after four weeks of therapy and exercises, Vaughn still walks with a pronounced limp and is nowhere near returning to practice. So team physician Charles Jackson will examine the knee to determine what course his rehabilitation should take.

"It's real frustrating," Vaughn said. "I had a lot of goals and expectations for myself this year, and this had to happen. It looks like it's going to be awhile, but all I can do is keep working and trying to come back."

Adickes Standing in Line

The Redskins were thrilled to find former Kansas City Chiefs guard Mark Adickes available as a Plan B free agent last spring, and even more thrilled to sign him. At the time, they said he would be a backup guard and insurance in case a starter got hurt.

Adickes knew signing with a team that had so many quality linemen was a gamble and he has been activated for only one of the Redskins' first four games. The one time he was active was against the Dallas Cowboys, and he didn't play.

"I knew this would be the deal," he said. "I'm here as depth and trying to fulfill my role. That means being ready in case I'm needed. I get a lot of reps during the week and like to think I'm doing my little bit by giving our defense a good look at the opponents' offense."

It's a drastic change for Adickes, who started 48 straight games for the Chiefs over a four-year stretch. However, he played only on passing downs the last four games last season, and when he was left unprotected, figured the Chiefs no longer wanted him.

He wasn't convinced otherwise even after Chiefs line coach Howard Mudd flew here to convince Adickes not to sign with the Redskins.

"It was a tough decision," he said. "There were a lot of different thoughts that went into it. But I really liked what I saw here. I liked Coach {Jim} Hanifan and Coach {Joe} Gibbs. I wanted to be with a classy organization and have a chance to get into a Super Bowl. I feel like I got that here."

Secret Service

Gibbs, responding to questions about beefed-up security at Redskin Park this week, said it may seem paranoid to an outsider but that spying still goes on and game plans do occasionally get passed around.

"Every game plan is different," he said, "and every week is different. For someone to know anything about what's going on has to help. The only reason I have security is that you owe it to your team. People got on me about the Super Bowl, but lots of times the person that would say something to someone else doesn't even know the person they're talking to. It could be a spectator or a bystander saying, 'Well, I'm just trying to do something to help the Giants.' "