CHICAGO, JAN. 9 -- The long wait is over. The Washington Redskins' most confusing and unpredictable season finally will be explained Sunday afternoon on the thawing artificial tundra of Soldier Field.

There, the Redskins will find out if they can play up to their admittedly high potential -- or if they will end their season the way they've played much of it, in an uncertain, unsatisfying manner.

At 12:30 p.m., the 11-4 Redskins will play the 11-4 Chicago Bears in a matchup of two teams who think they are much better than they have looked most of the season. They also are two teams who respect one another, but don't care much for each other.

With quarterbacks Doug Williams and Jim McMahon dueling and with running back Walter Payton playing what could be the last game of his storied, 13-year NFL career, it figures to be a memorable game.

Even better, it won't be played in a deep freeze. Temperatures actually are rising in Chicago. After a week in a sub-zero chill, the city will bask in temperatures in the low 20s Sunday, with slight winds, according to local weather reports. Both coaches have said stiff winds are more of a problem than cold temperatures, but the way things look now, neither should be a strong factor in the game.

So it may be without the freeze, or the Fridge, but this NFC semifinal between two division champions has added significance after Minnesota upset San Francisco today in the other semifinal. The winner Sunday will host the conference championship game Jan. 17.

"We pretty much had discounted the chance to play at home, but after Minnesota won, it was like a breath of fresh air," Redskins defensive end Charles Mann said tonight. "We now know everything is in our hands. It's like a dream come true. To us, it makes a world of difference to be playing for the opportunity to play at home."

Its featured players are Williams, starting in place of the demoted Jay Schroeder, and McMahon, starting for the first time since Dec. 6 after suffering a pulled hamstring. McMahon is the best thing the Bears have going for them; with him as their starter, they have a 28-1 record since 1985. (The loss was to Denver, 31-29, in November.)

But McMahon admitted this week he is not 100 percent healthy. "I'm not able to run full-speed," he said. "I don't think I've ever been 100 percent. I don't know what that feels like."

Williams' situation is entirely different. He is trying to prove he can win a game as a Redskins starter and beat a team he last played against in 1982 as a Tampa Bay Buccaneer. He is 3-0 in relief of Schroeder this season, but 0-2 as a starter. Yet he believes his -- and his team's -- time has come.

"I don't think we've played up to everybody's capabilities," Williams said. "I don't think we've gotten the respect we probably deserve, but, then again, maybe we don't deserve it the way we've been playing. So going to Chicago and winning, hopefully, will shed some light on us as a team."

It's not all that difficult to envision a Redskins win, despite the fact they are four-point underdogs playing on the road. This season, the Bears looked like their old '85 Super Bowl selves until McMahon was injured, then fell apart in a 41-0 loss at San Francisco and a 34-21 loss to Seattle. They ended the season with a forgettable 6-3 win over the Los Angeles Raiders.

The Bears have made nine lineup changes, including the benching of defensive tackle William (The Refrigerator) Perry. McMahon is back, but a question mark. Payton will start but has not been the Payton of old, unable to gain 100 yards in a game this season. Neal Anderson, the team's leading rusher, is out with a knee injury.

The Redskins privately believe the Bears might be ripe for an upset. It's the same philosophy they had a year ago, when they won, 27-13.

But last year the Redskins were rolling. They have been hardly impressive this season, but entered the playoffs with more momentum than Chicago by winning at Minnesota in overtime, 27-24.

To win, the Redskins believe they have to establish at least a minimal ground attack, something that has not been easy for them. The much-maligned George Rogers will start, but it's likely Kelvin Bryant, who averages 5.3 yards per carry and 11.4 yards per catch, will be the workhorse. He is too valuable to the Redskins to be on the bench, unless Rogers or backup Timmy Smith are running better than expected.

Last time, the Redskins beat the Chicago blitz for two touchdown passes. That was Schroeder throwing to Art Monk. This time, Schroeder isn't starting and Monk isn't playing due to a knee injury. So it's up to Williams to pick up the blitzes and Gary Clark, Ricky Sanders and Anthony Allen to get open deep, if possible. The Bears don't seem to be blitzing as much as they have in the past, Williams said, and even are playing some zone. If that's true, watch for Williams to throw short, where his touch is better than Schroeder's.

Williams has been sacked just seven times all season. The Redskins will be in trouble if the Bears get to him Sunday. Williams doesn't expect that. He has a plan: "Dip and dodge," he calls it.

Williams is playing his most important football game in eight years, since he led Tampa Bay to the NFC championship game after the 1979 season. His attitude can be summed up in three words: "What, me worry?"

"I don't think there's another way to approach it," he said. "Win, lose or draw, there is a tomorrow. The sun is going to come up Monday, whatever happens."

Redskins Notes:

Tight end Clint Didier and safety Clarence Vaughn were activated and tight end Joe Caravello and wide receiver Clarence Verdin were placed on the five-man inactive list . . . Eric Yarber and Darrell Green will return punts, Sanders and Allen will return kickoffs, said special teams coach Chuck Banker. Game rosters, Page B14