The San Diego Chargers are halfway to calamity at 3-5 with Dan Fouts' arm falling off. Five times they've given up at least 30 points. The news is that Don Coryell, ol' grouch face, is smiling.

This is not to say he is yukking it up. Football is serious stuff for the coach. Still, after Coryell said, "We could be 8-0," there came a quick smile of confession. "Or we could be 0-8, too."

Some folks call Coryell "Professor," as in Absent-Minded, because he can lock himself up watching film and forget the way home. So it's no surprise to hear him say of the semi-calamity, "I've learned to blank it out of my mind, to forget the losses and the standings. I'm only thinking of the game Monday night. Until a couple days ago, I didn't even know who we played the rest of the year."

Is he puzzled by the turn of events that has left the proud Chargers in such disarray?

"I accept it. I can accept it only because I know the players have put forth a good effort. Nobody is laying down or loafing. Because of an accumulation of circumstances, we are 3-5. There is no question we would have beaten Denver if we had Fouts, Chuck Muncie and those people (three other injured starters). I can accept it. It is just one of these damn things that happen."

And he smiled again, this time as if bemused, as if at age 59 he only now has learned it would do no good, considering the circumstances, to rail against invisible forces.

A man so plainly emotional--"He can have you crying with a pep talk," said Joe Gibbs, who studied at Coryell's knee--might be moved to anger, or to despair, over circumstances that conspire to reduce a championship-level team to mediocrity: injuries, desperately poor defense, 11 lost fumbles, 15 interceptions and, to quote Coryell, "a couple officials' calls."

But here is Coryell at ease. Or is it, perchance, a pose? Lombardi put the lash of his tongue against his players' backs when they won; in defeat, he more likely would sing sweetly of their good work to reassure them in their moments of doubt.

"I try to be consistent, to do the same things, win or lose," Coryell said. "If somebody plays well, I don't keep it a secret. If they play bad, I let them know that, too, win or lose. No one person wins or loses a ball game. It takes 20 or 30. Everybody wins and everybody loses. We're all in this damn thing together."

Don Meredith sized up Coryell's face one Monday night and said, "Sumbuddy oughta tell Don it's onla a game." Coryell's face, on game days, speaks of pain. It not only speaks, it screams bloody murder. His delicate brow twists, his cerulean eyes go black, his lips pucker as if he had overdosed on persimmon. Agony, thy name is Coryell.

This is not to nag at the man. To tell a football coach that it's only a game is, as Joe Paterno's daughter observed, like telling a carpenter whose new house has fallen down, "Relax, it's only a house." Coryell's thousand game faces tell horrific stories of a coach's house falling down.

What distinguishes Coryell, however, is that most times his teams have been winning when the television cameras move in for the obligatory look-at-the-guy-suffer shot.

In his five seasons at San Diego, the Chargers have won three AFC West titles. Coryell's 46-19 regular-season record from mid-'78 to this season was second only to the Cowboys' 47-18. The Chargers became so much the symbol of offensive sophistication that they were raided for brains (Ray Perkins to the Giants/Alabama, Gibbs to the Redskins).

All the Chargers needed in order to win a Super Bowl (everyone agreed) was a defense that didn't lose it along the way. Just be mediocre, not terrible. But in five playoff games in those division-championship seasons, the Chargers gave up an average of 26 points. Tom Bass, their current defensive coordinator, their third in three years, took the job last season.

As irony would have it, the Chargers' defense now seems to be rising toward mediocrity just when the offense is falling in on Coryell's head.

"On a scale of zero to 100," Bass said of his defense, "we were at zero when we began two years ago. Now I'd say we're at 70 or 75 percent of what I'd like to do. But it's been difficult as a team. For a while, we were not playing well on our side of the ball. Now our offense is hurting physically."

The 3-5 record is Coryell's worst start since 1973, his first season with the St. Louis Cardinals. So with the Super Bowl champion Redskins coming to town Monday night . . . with games to play against Pittsburgh, Dallas and the Raiders (twice) . . . with Fouts, Muncie, Eric Sievers and James Brooks injured. With all this, it seems the last person smiling around here would be ol' pain in the face, Don Coryell.

When did he last start so poorly?

"I was hired after four games of the '78 season and we lost three of our first four games. So, maybe then."

Another smile, a little one, call it hope.

"Then we won seven of our last eight."