It's not easy, figuring out the Dallas Cowboys and the Washington Redskins.

In the fifth game of the 1982 regular season, Dallas won, 24-10, at RFK Stadium. The Cowboys sacked quarterback Joe Theismann seven times and forced him to throw three interceptions because of a crazy blitzing pattern that brought in linebackers and safeties and ruined the Redskins' unbeaten record.

Quarterback Danny White completed 21 of 29 for 216 yards and one touchdown and when the Redskins closed within 17-10 in the fourth quarter, White ran out of punt formation for 21 yards and a first down that left Redskins' chins taking root in the RFK sod.

"That was like night," Theismann remembers. "Then came day."

Ah, day. In the NFC title game, the Redskins sent Dallas spinning, 31-17, and sent RFK rocking. John Riggins, held to 26 yards in the first Dallas game, ran for 140 yards and two touchdowns on 36 carries. Dallas was held to 65 yards rushing and, for the second straight time, the Redskins held Tony Dorsett to 57 yards rushing.

Defensive end Dexter Manley sent White into dreamland and out of the game, knocking him unconscious with a vicious second-quarter pass rush. Reserve Gary Hogeboom entered and produced, until Manley defelected his pass and defensive tackle Darryl Grant intercepted it and ran 10 yards for the tocuhdown that made it 31-17 with 6:55 left.

"The difference in Washington from the first game to the second game," says Dallas Coach Tom Landry, "was Washington's confidence."

Perhaps this is why Coach Joe Gibbs, says, "I think it will take the same emotional pitch from our fans and our players in the stadium to beat Dallas. The question is: can we get back to that emotional effort?"

So, now what?

The Cowboys' White undoubtedly will test rookie left cornerback Darrell Green Monday night. And, as always, Dorsett will zigzag about, trying to gain more than 100 yards for the 34th time in what will be his 100th career game.

Calculations flow freely now inside the Cowboys' computer as well as underneath the fedora of Landry, who finished 7-7 against George Allen's Redskins, 4-2 against Jack Pardee's and is now 3-1 against Gibbs'.

Landry knows that Green and strong safety Curtis Jordan, a seven-year veteran, are replacements for holdout Jeris White and Pro Bowl starter Tony Peters, who now awaits sentencing on drug charges.

"They seemed to fit into the (Redskins') system so far," Landry said of Green and Jordan. "Of course, teams are looking at so many people in the preseason, they don't really test (opposing teams') weaknesses."

Though the Redskins' defense prides itself on a system of movements and complexities, Landry said, "the system can never overtake the individuals in it."

To a man, the Redskins say they must generate a pass rush and, most of all, they must stop Dorsett. Dallas is 31-2 in games in which Dorsett has run for more than 100 yards. Historically, Washington has played Dorsett tough: against the rest of the NFL, Dorsett averages 4.7 yards per carry. Against the Redskins in his seven-year career, he averages only 3.7 yards per carry.

Last year, Dorsett gained 114 yards in 41 carries against the Redskins: a 2.8-yard average. Dorsett's rare cutback ability creates a problem of defensive overpursuit.

Dallas uses enough offensive movements and formations to drive opposing defenses batty. "It takes away defensive aggressiveness," says Redskins free safety Mark Murphy. "It makes you think about shifting all the time. That's why teams play a basic (defensive) game against Dallas. I'm sure that's what we'll do."

In a statement that surely will make Richie Petitbon, coach of the Redskins' defense, smile, linebacker Rich Milot adds, "Dallas is a finesse offense and the way to beat a finesse offense is with power."

And what of the Redskins' offense versus Dallas' flex defense, which, alternating flexed strength from side to side, is so cramping to Everyman's running attack?

"The key," Theismann says, "is to gain three or four yards on first down. To play the Dallas Cowboys, people feel you have to throw on first and 10 because of the flex, when they have both tackles off the ball, both ends up, five people who are one-and-a-half yards off the football.

"The key to beating the Dallas Cowboys," Theismann says, "is not getting third-and-long."

That's when all the speed in the Dallas secondary and all those funky blitz formations make Dallas Doomsday tough. "They did things in that first game last year that they had never done before, like blitzing nine guys at once," said Redskin guard Mark May. "We changed things in the second game (last year). If they ever did that again, we'd be ready."

The Dallas front four--from left to right, Ed (Too Tall) Jones, John Dutton, Randy White and Harvey Martin--is aging, but is also terrifically talented. White is the smallest, at 6 foot 4, 258 pounds and the most inexperienced with only nine years' experience.

"None of them are munchkins," May says.

Likely, the Redskins will try to establish some ball control by way of Riggins. And, just as likely, Dallas will be waiting for Riggins, flexing away on the other side.

"If Riggins keeps us tied down to the running game," says Landry, "their passing game will get better, too."

Dare one neglect the importance of the special teams. Simple enough, the Redskins kick return team haunted Dallas last year. Mike Nelms returned five kicks for 129 yards in the first game; he returned four kickoffs for 128 yards in the title game, including a 76-yard return to the Dallas 21 after Dallas had closed within 14-10 in the third quarter. Nelms' return led to a crucial touchdown.

"I thought the big play in the championship game was Nelms' return of the kickoff," Landry said. "We had them back on their heels in the third quarter. It changed the complexion of the game."

"Good contest," Theismann projected for Monday night. "Nothing more, nothing less. If we win, it won't make our season. If we lose, it's not the end of the world."

Theismann smiled. To emphasize that this game is not the Only Game, he added, "Even if we lost, 15-1 is not a bad record."