Chicago Bears quarterback Jim McMahon will miss the rest of the 1984 season, including the playoffs, because of the kidney lacerated a month ago against the Los Angeles Raiders. But there was good news for Coach Mike Ditka, as Bears President Mike McCaskey told the Chicago Sun-Times Ditka has done an excellent job and "I fully expect he'll be coaching the Bears next season."

The Bears announced yesterday that McMahon, their No. 1 quarterback, will not play the last two games or any playoff contests the Bears have this season. But he will be able to play in the 1985 season.

"It's frustrating and I'm disappointed," said McMahon, who played most of the season with a fractured hand. "But I pretty much saw it coming. It's healing, but at this point there is no way I can play."

Ditka, whose contract expires this season, has said he might not be asked back. But, McCaskey said, "All the signals to me have been that Mike very much wants to stay. I would be tremendously surprised if something else pops up" . . .

Alex Spanos, owner of the San Diego Chargers, said a published report that he was trying to woo Redskins General Manager Bobby Beathard to his team was "absolutely ridiculous. I have no idea where it came from," Spanos said about an article in Sports Illustrated. "I don't even know Bobby Beathard."

Beathard told the Associated Press the article was "a rumor" and that he had not talked with anybody from the Chargers. He said he plans to honor his Redskins contract, which covers two more years after this season.