Not a soul under the Redskin Park roof yesterday seemed to see the slightest chance in Cowboy Heaven that running back John Riggins won't play Sunday at Dallas.

"About the only way I think John will miss this game," tackle Mark May figured, "is if he gets struck by lightning."

And tackle Joe Jacoby said, "John's always there when we need him. How much do we need him now? Two games to go, we haven't won the division yet. I think that question answers itself."

"This is Riggo's time of year," veteran defensive tackle Perry Brooks said. "December and January are his months. Just like October is Reggie Jackson's month in baseball."

Dallas Week moved into full stride yesterday as freezing weather brought another kind of hail to the Redskins.

Riggins seemed in full stride, too. The 35-year-old carried the ball on several practice plays and appeared fit, a Diesel with a healthier set of shocks. Riggins, who does not speak with the media except after games, has been suffering from pain in his lower back and hips and spent the weekend in traction at Sibley Hospital.

Asked if he expects Riggins to play Sunday, the ever cautious Coach Joe Gibbs said, "Yeah, that's my gut feeling . . . It's been three or four weeks since John has been here able to take work on a Wednesday."

Gibbs said this is the Redskins' most important regular-season game in his four years as coach, what with his team in a three-way tie for first place in the NFC Eastern Division with Dallas and the New York Giants with 9-5 records and two games apiece left.

The last time the Redskins played a game this late in the regular season that meant make or break to their season (and not just home field advantage) was the 1979 closer when Jack Pardee was Washington's coach.

That 1979 game was when the Cowboys rallied to beat the Redskins, 35-34, at Texas Stadium. The Redskins have miserable memories of how it got away from them after Riggins made a 66-yard touchdown run, longest of his career.

They remember how Dallas quarterback Roger Staubach threw an eight-yard touchdown pass to receiver Tony Hill with 39 seconds left, completing Dallas' rally from a 34-20 deficit. They remember how Redskins kicker Mark Moseley lined up for a potential game-winning 59-yard field goal, but wasn't allowed to kick it because the officials insisted time had expired.

They remember how, even with the loss, they could have won the playoff wild card with their 10-6 record, considering they had begun that day with a 33-point advantage over Chicago in what was then the most crucial tie breaker for determining the wild-card spot: most points for the season.

The Bears beat St. Louis that day, 42-6. Some Redskins said the Cardinals were quitters. No matter.

The playoffs were gone for the Redskins and their pride was damaged further when Dallas defensive lineman Harvey Martin (now retired) threw a funeral wreath into the Redskins' postgame locker room.

"Harvey screamed out something negative, too, when he did that," Brooks recalled. "He always thought he was God's gift as a football player." (Martin later apologized.)

Moseley has one other recollection: "After the game, fans were hanging down over the tunnel (to the locker room). One guy dropped his sunglasses. I picked them up to give to him and when I looked up the fan spit in my face. I couldn't believe it. Neither could the policeman next to me. I just gave the policeman the glasses and kept walking."

That 1979 playoff situation was comparable with the current situation. The Redskins could lose to Dallas on Sunday, then beat St. Louis at RFK Stadium Dec. 16 and, depending on other games, have a mathematical chance of qualifying.

But the Redskins aren't looking at it that way. "This is all or nothing," Gibbs said. And defensive tackle Dave Butz added with certainty, "If we don't win Sunday, we won't make the playoffs."

Mostly, there was a confident air at Redskin Park, with the standard bit of the unusual that always seems to pop up during Dallas Week.

Some prankster invited a female stripper to embarrass second-year quarterback Babe Laufenberg on his 25th birthday. After the woman stripped to a bikini, during the team's break for lunch, Laufenberg showed a keen sense of humor for a player on the injured reserve list and ineligible to play.

Said he, "I think Tom Landry might have planted her here to take my mind off the game Sunday."

Quarterback Joe Theismann said of the return of Riggins, who has missed two of the last four games and had just three carries in one of the two he did appear in, "I think it's important to have John back. It's the first time we've had our whole offense back since who knows when."

How about 10 weeks? This marks the first time since before the Redskins' 26-10 victory over New England in Week 4 that Riggins, wide receiver Charlie Brown and running back Joe Washington all have been on the field and on the active roster at the same time. (Center Jeff Bostic is the only starter not back; he is out for the year with a knee injury.)

"Yeah, but we've seen each other passing between the trainer's room and the locker room," Washington cracked.

Perhaps it is this offensive reunion that led to the Redskins' seeming burst of confidence yesterday. Moseley was saying, "I think you'll see the old Redskins this week, the team that everybody expects us to be, the team that we were last year. Why? Because everybody is back together now."

And May, the offensive tackle, added, "If everybody is healthy and ready to go, it could be an awesome game for us. When we play at our best, I don't think anybody could beat us." -- --

Running back Washington admitted he has soreness in his ribs, caused when a player fell on him during the 31-17 victory at Minnesota last Thursday night . . .

Free safety Curtis Jordan said he went to New York Tuesday to meet with Commissioner Pete Rozelle to appeal the $500 fine Rozelle imposed for a "flagrant" hit on New England tight end Derrick Ramsey.

"He said that he saw my point and that he could see why I did what I did," Jordan said. He added that Rozelle will study the case further, then will inform Jordan of his final decision.