On Bill Arnsparger's first day of work for the Washington Redskins, he and Coach Norv Turner said defensive coordinator Mike Nolan remains in charge of the team's defense and Arnsparger is on hand to help, not supplant, Nolan.

"Mike is the defensive coordinator and I'll work with Mike, just like all the other coaches," Arnsparger said yesterday.

Said Turner: "Mike will call the defenses. It would be asking a lot of Bill to come in here and do it right away. Most of the decisions each week are made Tuesday and Wednesday in game-planning meetings. I have it with [offensive assistant coaches] Terry Robiskie and Bobby Jackson. . . . Who cares who makes the actual play call? It's the process of working together during the week to come up with a plan that counts."

Still, the Redskins are counting heavily on Arnsparger, the 72-year-old defensive guru with nearly four decades of coaching experience, to help fix a defense that is ranked last in the NFL. After arriving in town Monday night, Arnsparger was at Redskin Park at 5:30 a.m. yesterday for a meeting with Turner. He spoke to owner Daniel Snyder and spent most of the day in coaches' meetings on an off day for the players. He's scheduled to participate in practice today.

After studying tapes of the Redskins' first four games, Arnsparger said he is convinced the team has enough talented players to succeed on defense.

"I don't think there's any question about that," said Arnsparger, who was hired by the Redskins last week and given the title of defensive specialist. "There's ability here and talent here, and there are people working hard here. We just have to continue working with it. You have to continue to stress the things that are important."

He and other Redskins coaches have begun discussing some wrinkles they plan to have in place for Sunday night's game at Arizona, but Arnsparger reiterated he doesn't foresee any major changes. He talked about taking a back-to-the-basics approach.

"It's nothing magic," Arnsparger said. "It's nothing new. It's just basic to being successful. . . . The basics remain the same. You have to line up right, know your assignment and carry that assignment out correctly and aggressively."

Arnsparger never has been tied to a particular defensive scheme, and NFL people say he has been so successful largely because he always has adapted to his team's personnel.

"I heard about it the other day and I said, 'They're going to be a lucky team, because he's brilliant,' " said Dick Anderson, who played safety for Arnsparger in the 1970s with the Miami Dolphins. "We had total confidence every time he called a defense. He puts you in the right situation at the right time."

The Redskins are convinced their defense will improve. They talk about the defense playing well for long stretches, then botching a few plays and surrendering big yardage. That can be fixed, team officials maintain. If that happens, the Redskins--who are tied for first place in the NFC East with a 3-1 record--believe they could be a Super Bowl contender in a conference without a dominant team.

"The best thing we have going for us is, our players really want to be good," Turner said.

Former Redskins linebacker Matt Millen said there is another reason to believe the defense will improve.

"Well, they can't get worse," said Millen, now a broadcaster for Fox.

"You have to have little victories," Millen added. "When you're last, you can't say you want to be in the top five. You say, 'Let's be 25th.' . . . There's an answer in there someplace. But I'm not qualified to give it because I'm not there every day. Arnsparger will help."

Millen, like those at Redskin Park, targets the play of the club's new starting linebackers--Greg Jones, Shawn Barber and Derek Smith--as one of the main problems. Unlike those at Redskin Park, Millen says the defensive line's play also must improve.

"They're young in spots," Millen said. "They're young at the one corner [with rookie Champ Bailey] and young at linebacker. They'll get better, but that takes time. . . . The linebackers are faster, but sometimes that just means they run faster to nowhere. . . . Up front, they have to play better. That's still a disappointment, it seems to me."

The Redskins have six former first-round draft choices starting on defense, four on the line, and they opened training camp with Nolan promising to take an aggressive approach. The Redskins figured that with Bailey and veteran cornerback Darrell Green, they could cover opposing wide receivers one on one and devote enough manpower to going after quarterbacks with abandon. The problem is, they've given up numerous big plays while surrendering 29.5 points and 433.5 yards per game.

"It's hard to determine what aggressive is," Millen said. "What's widely assumed is, it means you blitz more. But if you don't have guys who are good blitzers, it's not going to work. . . . In theory, they have enough talent."

Millen said he thinks the Redskins will begin taking a more conservative approach in an attempt to eliminate big plays.

"You give up the underneath stuff," he said. "You don't give up the big stuff. Most offenses will stall on their own. . . . Do they have a pass rusher? No. So you have to sit back and make teams throw underneath. The problem is, [Bailey] doesn't play zone well. He's too soft in zone, and Darrell is better when he gets right up on you too."