Last year, the Redskins expected New Orleans quarterback Archie Manning to pass against them until he couldn't lift his arm. Instead, the Saints surprised Washington with a conservative run-oriented game plan that led to an upset victory.

This year, the Redskins again are preparing for a heavy Manning barrage. Coach Jack Pardee is predicting as many as 45 passes from the beleagured Saints' starter, who has survived an 0-7 start to remain one of his team's few bright stars.

This time around, however, Washington doesn't expect to be crossed up by any surprise play-calling for the 1 p.m. game in RFK Stadium (WDVM-TV-9). The Redskins (2-5) are rated 10-point favorites.

"I'm sure they will try to run the ball, they did it well enough on us last year," said free safety Mark Murphy. b"But I think it will come down to how well he can pass against us. That's been their pattern so far this season."

Manning is a 64 percent thrower this year. How well he does in matching up with the league's No. 1-ranked secondary will depend greatly on the play of Murphy, who has improved steadily from last year, his first as a starter.

"Murphy has really come on," said Richie Petitbon, the Redskin secondary coach. "He's much more aggressive than last year. He was good last year, but cautious. He didn't want to make mistakes. He didn't want to get beat. But he's more of a gambler this season and that means he can have more big plays, which we need out of his spot."

Murphy's emergence as a steady performer makes an already talented secondary that much tougher for Manning to crack. Where does a quarterback turn? Does he work on all-pro cornerback Lemar Parrish? Or how about cornerback Joe Lavender, who is enjoying what Coach Jack Pardee feels is his best year? Or what about Tony Peters, the man the staff feels is good enough to have beaten out one of the best strong safeties in league history, Ken Houston?

"Being ranked No. 1 against the pass is really a bit misleading," Pardee conceded. "That just means that teams have been running against us well enough that they don't have to pass as much. And it also means that teams have been ahead of us enough so they didn't have to pass much.

"If we can play like we did last week against St. Louis, and start getting some leads on people, we will see more passing against us and I'm sure our ranking will drop. That doesn't bother me. I'm more concerned about the percentage of completions and the yards per pass anyway."

Opponents have completed just 47 percent of their passes on Washington, for 138 yards a game, while having 14 tosses picked off. The only crack in the Redskin defense has been its vulnerability to long plays; the team has given up half its passing yardage on one-fourth of the completions. But that is part of the risk in man-to-man, aggressive coverage.

"We just don't want to give up any bombs by Manning," Pardee said. "We need a good pass rush and not let him have a lot of time." The Redskins found out last week against the Cardinals, when they sacked Jim Hart six times, how effective consistent pressure can be. And Manning already has been sacked 18 times.

Preventing bombs is one of Murphy's duties. He normally is the last line of defense in the secondary, which tends to make someone as conscientious as Murphy a bit cautious. He admits that last season, he was too cautious.

"I wanted to make sure I didn't commit myself too fast on plays and not be able to cover up," he said. "I didn't gamble as much.

"I'm much more relaxed this season, and I feel much more comfortable. I can react to things more naturally. It comes down to experience. Einstein would have been a great player if he could have just studied films and worked a computer but you have to do it on the field. I have better concept of what we are doing, and I think I know better now when I can go for an interception or force hard on a run and not worry about being pulled for a mistake."

Murphy's statistics show his improvement. He leads the club in total tackles (75 to Rich Milot's 45) after leading the Redskins in the same category last season. But he also has intercepted three passes, equaling his 1979 total, and surely he has surpassed his previous high for hard hits.

The best in that last category came in the Cardinal game. Receiver Pat Tilley had broken free deep in the secondary and appeared ready to pull in a possible touchdown pass. But Murphy, closing from 15 yards away, leveled Tilley with a devastating tackle just as the St. Louis player was catching the ball.

Tilley dropped the pass and lay on the ground for a couple of minutes before walking to the sidelines. It was the type of play Murphy would not have made last year.

"I didn't think I had hit him quite that hard," said Murphy, a scholarly, soft-spoken person who hardly fills a tough-guy image. "But my wife got mad at me for walking away from him when he was on the ground. She thought I should have seen how he was."

Manning, meanwhile, will be matching his top-flight receivers, Wes Chandler (29 catches) and Ike Harris (18), plus three tight ends, against a Washington secondary that uses two nickel backs (Jeris White or Mike Nelms) depending on the game situation. The Redskins have both the size and, with Parrish, the quickness to employ a complex group of coverages.