CARLISLE, PA., AUG. 20 -- The Washington Redskins had so much trouble running the ball late last season that Coach Joe Gibbs made it a training camp priority. Now, halfway through the preseason schedule, the Redskins are still sluggish and inconsistent.

The question they may now be asking: Do August failures translate into September failures?

Gibbs has kept much of his offense under wraps, meaning that while the Redskins wanted to win preseason games their primary objective has been to get ready for the Phoenix Cardinals on Sept. 9.

There's also the matter of playing time. The coaching staff has looked at several combinations in the backfield and the offensive line, and shuffling personnel hasn't helped get much going.

Finally, there may be the matter of opponents. While they say Friday's 81-yard rushing effort against Pittsburgh was a bad night, the Atlanta Falcons the week before simply showed them more defensive looks than they prepared for.

"It meant more to them than to us," a Redskins official said, referring to new Falcons coach Jerry Glanville's injection of emotion on the other sideline.

Such could also be the case Saturday night in Cleveland because the Browns also throw a lot of men at the line of scrimmage and try to stop the run first. If the Redskins come out of that game with only 50 yards rushing, they may not be surprised. But that defensive philosophy could open up a big passing effort for Mark Rypien.

So while the Redskins don't like their numbers -- 117 yards and a 2.49 per carry average after two games -- they've emphasized that the problem may not be as serious as it appears. The bigger question may be: Who will line up in that backfield against the Cardinals?

Earnest Byner, who didn't play Friday because of a sore hip, entered camp as the starter and has done nothing to give up the job, playing one game and gaining 27 yards on five carries.

Meanwhile Gerald Riggs, the starter until getting hurt last season, has run 16 times for 35 yards, a 2.2 average. Riggs has appeared slow and tentative getting to the line and for all the world like a man who has already carried the ball 1,788 times in his pro career.

Yet the Redskins are quick to point out that Riggs had about the same kind of preseason last year after being acquired from Atlanta, then went out and gained 111 and 221 yards the first two games.

He had played like a man worth a first- and second-round draft pick and Gibbs said: "He gave us exactly what we wanted. But we need durability. That's all that separated Gerald from an all-pro season. When healthy, he was great."

Likewise, the Redskins say it's too quick to judge Plan B signee James Wilder. He has zero yards on eight carries, but the Redskins don't want to judge him until giving him a solid quarter or two to get into the rhythm of playing.

"Right now, it's a little bit of everything," Gibbs said. "We had some situations where the line didn't execute and some situations where the back should have gotten more yards."

It's a particularly tough camp for Riggs, in the position of trying to prove he can do what he has spent most of his career doing.

He knows that last season's nagging heel injury raised doubts about whether he could still be a top-flight running back even though he was among the league leaders when he got hurt in Week 7. The arch was slow to heal, and by the time Riggs was ready to play, the Redskins had become comfortable with Byner as a starter and a passing game as the offense of preference.

All of that has stung Riggs, who has prided himself on being a healthy, durable back, and believes that at 29 some of his best seasons have yet to be played.

"Last season was a very bitter experience for me," he said. "The year before hadn't been great, and then . . . I've played with a lot of aches and pains in my career, but this was different. It was severe and it just wouldn't go way. You know people start to wonder about you. I know what I'm capable of and I'm in a strange role this camp. I've been around nine years and now I'm having to come in here and show it. I accept the challenge. I feel I'm on track. I'm a little rusty, but so is everybody else."

The worst part is that while Gibbs and his staff are trying to figure how to use all the backs, the backs are trying to figure how they'll be used. It's an odd situation for Riggs. He spent seven years in Atlanta and for the last five was the main running back. He came to camp knowing he'd get his 300-plus carries and went about preparing for the pounding.

"For me personally, I've always gotten ready by getting a lot of repetitions," Riggs said. "This week was the first time I've really been hit a lot, and you've got to have that to get ready. Right now, it's kind of weird. It's like we're getting a good drive off the line of scrimmage, but we're not getting many yards. I'm a little worried about it. I'm sure it'll come around, but you can't just sit back and say it'll happen."

That's even more true for a team that can't afford a slow start. The Redskins play division opponents seven times in the first nine weeks.

The Riggs-Byner competition has left Wilder almost in the background -- an unusual place for the NFL's fifth-leading active rusher, the heart of the Tampa Bay offense most of the '80s. He knew there would be competition and perhaps less playing time when he signed with the Redskins last winter and knows that better than ever today.

"We've got probably more quality backs than anyone," he said, "and everyone wants a piece of the action. It's going to be hard to keep everyone happy, but that's not my concern. I need to keep getting ready and learn everything."