Quotes of caution have been heard around Redskin Park all week.

After consecutive losses had transformed the Redskins' season from a 5-2 flight into a 5-4 fight, veteran defensive end Tony McGee was saying, "It's time for us to circle the wagons."

And Coach Joe Gibbs was adding, "We haven't been playing like ourselves for two weeks. My biggest concern is ourselves."

Tonight at 9, the Redskins will play the Atlanta Falcons before the 137th consecutive regular-season sellout at RFK Stadium (WJLA-TV-7). Since both St. Louis and Dallas lost and the New York Giants won yesterday, a Redskins victory would create a four-way tie for first place in the fickle and congested NFC East.

"If we lose this game," linebacker Mel Kaufman said, "it's one foot in the grave for us . . . You don't want to go 10-6 or something and then have to worry about tie breakers."

Meanwhile, trainer Bubba Tyer said that quarterback Joe Theismann's sprained left thumb should not create any problems tonight. Tyer said Theismann, who is right-handed, sprained the thumb while handing off to fullback John Riggins in practice Friday. "He gripped and threw the ball well today without any problems," Tyer said. "He'll either wear a little piece of tape or nothing at all in the game. He's rarin' to go."

The Falcons are a troubled team. They are 3-6; they have lost three straight games, after already having lost their finest running back (William Andrews) and their finest wide receiver (Billy Johnson) to season-ending injuries.

The Atlanta owner, Rankin M. Smith, recently unsettled the Falcons by wondering aloud whether some of his personnel were playing from "paycheck to paycheck;" the team's attendance is down and, after a 35-10 loss to Pittsburgh last week, an Atlanta newspaper headline termed the Falcons' effort "a joke." Tonight, to make matters even more difficult, three of the Falcons' offensive linemen are expected to play with casts on their hands.

No wonder that oddsmakers have made the Falcons 11-point underdogs tonight. None of the Redskins' next four November opponents (Detroit, Philadelphia, Buffalo and Minnesota follow) has a winning record, either.

"We really still have a good shot of making the playoffs," said Redskins linebacker Rich Milot. "A lot of people look at our schedule ahead -- at the won-loss records and statistics -- and say that (the opponents) are not physical or powerful teams. Well, I think that (kind of thinking) is what could have gotten us in trouble last week when we lost (37-13) to the Giants.

"We can't afford to lose another game. It's that simple. And we definitely can't afford to let what happened last week happen again, no matter who we are playing."

Perhaps the most potentially destructive thing of all tonight for Atlanta is that its rush defense rates 26th in the 28-team league. The Redskins average 157 yards rushing per game (second in the league to Chicago's 158-yard average); Atlanta yields an average of 151 yards rushing per game.

Expect Riggins, who has had at least 28 carries in five of nine games this season, to run left, right and often tonight. Pittsburgh's Frank Pollard ran for 111 yards against Atlanta last week. Earlier this season against the Falcons, the Rams' Eric Dickerson rushed for 107 yards, the Vikings Darrin Nelson gained 96 and the 49ers' Wendell Tyler picked up 99 yards. Only Dickerson (19) had more than 15 carries.

Meanwhile, the Falcons' offense is the mirror image of the Redskins' one-back formation and has produced some glossy numbers: quarterback Steve Bartkowski has completed a league-best 68 percent of his passes and has thrown for 10 touchdowns with nine interceptions. Gerald Riggs has replaced the injured Andrews and has run for 828 yards, including 202 in a season-opening victory over New Orleans.

"Statistics are a matter of mathmatical mumble-jumble," said Coach Dan Henning, a former Redskins assistant. "The game is based on how many points you score.

"We haven't traded for or drafted players on offense and we've had a great deal of attrition. Just as in the case of the Redskins or the Chargers or whomever, there is no way to account for injuries when you take away football players in the middle of the season. It becomes a scrambling game."

The biggest loss to the offense was Andrews, who finished second to the Rams' Dickerson last year with 1,567 yards rushing. Andrews also caught 59 passes for 609 yards.

"Andrews is a very special runner," Richie Petitbon, Redskins defensive aide, said. "But I really don't think there is much of a dropoff with Riggs, though. He's a very physical runner."

There are different explanations for the Redskins' sluggish efforts over the past two weeks, which followed the euphoric-high of the 34-14 victory over Dallas.

Some point out that, besides the 11 players the Redskins have placed on injured reserve since the original 49-man roster was declared, many other players have been continuing to play with painful injuries. Defensive tackle Darryl Grant has a hamstring pull and linebacker Kaufman has a hip injury, to name a few. (Tight end Don Warren is expected to play Monday, despite a deep thigh bruise; rookie Anthony Jones would fill in if Warren is unable to play.)

Gibbs has pointed out that the defenses of St. Louis and the Giants added new twists that the Redskins hadn't been preparing to face. He said Atlanta might try a few new wrinkles, too. "I'd say that after the last couple of weeks," Gibbs said, "it's on my mind."

McGee says one misconception has developed over the past two weeks.

"A lot of people feel that we don't have the desire right now. I've heard people say that, but I don't really feel that's accurate," McGee said. "We've been to the Super Bowl twice. We know how nice it is to go. We want to go again."

The Redskins defeated the Falcons, 37-21, in Week 14 at RFK Stadium last year, building a 34-0 lead late in the third quarter while being seranaded with "We want Dallas" cheers.

"I just looked at the films of the game here last year," Gibbs said, "and at that time of the season we were really playing aggressive, hard and good. But right now, at this point of this season, they are stuggling like we are."