The Washington Redskins will be in Philadelphia today, hoping to show that exhibition-game scores are meaingless.

The Redskins were 0-4 in a preseason marred by poor secondary play, an inadequate pass rush, spotty pass protection and what Coach Joe Gibbs called, "Our inability to make the big play when we need it the most."

Unless Washington corrects most of those problems quickly, it will have a hard time beating any National Football League team, much less one with the talent of the play off-caliber Philadelphia Eagles, who are favored by 6 1/2 points.

"My major concern? The schedule that has us opening in Philadelphia," said Gibbs about this 1 p.m. game (WDMV-TV-9, WMAL-Radio-63). "I don't think anyone can dispute that this is a really tough, tough opener for us."

But safety Tony Peters, who should be more active this year correcting Washington's problems against the run, said that no Redskin "is panicking about what's happened. It's all correctable. Preseason still is preseason. We are starting off 0-0 like everyone else, and that's how we're approaching this game."

Gibbs is convinced this team is better than the 1981 Redskins, who finished 8-8 after an 0-5 start. But he realizes it is foolish to talk too loudly about that improvement until his team wins a game.

"I think we've upgraded our receivers, our backup quarterback, our offensive line, our punting and I hope that experience has improved our defensive ends," he said. "Tony McGee will help the pass rush, Larry Kubin helps the linebackers and Vernon Dean is a good addition to the secondary.

"But unless we start winning, all that is up in the air, because everything in football is based on winning. Besides, this is the kind of game we've had a tough time winning. Last year, we couldn't beat a good opponent away from home."

Last year, the Redskins manhandled the Eagles for a half in Philadelphia and wound up outgaining them, 337-221. But Washington lost, 36-13. At RFK Stadium, Philadelphia gained more yards, 416-176, but lost the rematch, 15-13.

Both teams have changed since that second game.

The Eagles traded away standout nose guard Charlie Johnson and their defensive front has not been playing well. But Coach Dick Vermeil brought back offensive specialist Sid Gillman, who has introduced the short-range pass to a more versatile Philadelphia attack.

"One thing that worries you is the unknown about the Eagles," said Defensive Coordinator Richie Petitbon, who will use a new 3-4 defense on second and-long downs and a new 33 nickel (three linemen, three linebackers) alignment on some third-and-long situations.

"They did so much in preseason, but we aren't sure what they will use against us in this game. This is one of the problems with an opening game -- receiver Charlie Brown, tight end Mike Williams, punter Jeff Hayes and Dean -- will make their pro debuts. Mark May will play his first game at guard after switching from tackle. McGee, obtained to complement the pass rush of fellow end Dexter Manley, has been a New England Patriot most of his career. In all, there are 17 different names on the roster this year compared with the opening game last season.

One of those new names, however, is not by choice. Joe Washington is out for at least four games after knee surgery. John Riggins will replace him, although Wilbur Jackson also will play frequently in the Redskin one-back set.

"It's just difficult to measure how much effect Joe's loss will have on us," Gibbs said. But Gibbs acknowledges that the game plan for the Eagles, which was pretty much set before training camp started, had to be altered considerably after Washington was lost.

The Redskins have to live without Washington's quickness, but just as lmportant, they will have trouble replacing his pass catching coming out of the backfield. When the team played well last year, those short passes were a major reason.

Quarterback Joe Theismann will be working against one of the League's five best defenses, even without Johnson. That Eagle unit had a shaky preseason pass rush (six of eight sacks came in one game), but otherwise it was extremely solid.

Quarterback Ron Jaworski, who suffered most by Gillman's one-year absence, didn't throw an interception in four preseason games. He has a new starting wide receiver, ex-Charger Ron Smith, and fullback, Perry Harrington. Vermeil made sure Wilbert Montgomery was healthy for this game by hardly playing him in the finale against Pittsburgh.

The Eagles have tried to correct what they perceived as a receiving problem by also adding draft choices Mike Quick (North Carolina State) and tight end Lawrence Sampleton (Texas). Quick backs up Harold Carmichael and Sampleton is behind starter John Spagnola, who has replaced the waived Keith Kreole.

Vermeil cut kick returner Wally Henry, the goat of last December's playoff loss to the Giants. Henry will be replaced by second-year halfback Calvin Murray and free agent Mel Hoover.

The Redskins made one change in their taxi squad, activating safety Greg Williams.