Gustie Marie Houston, whose husband, Ken, may be the best strong safety in professional football, asked him a good question the other night. "When did you first know you were a good player?" she said, and Ken Houston said, "I'm not."

Well, now. On May 15, 1973, George Allen, the Redskins' coach and chief magician, performed one of his greatest feats of pigskin legerdemain. He transformed five guys named Joe into one named Ken Houston. It was a trade of five never-will-bes to the Houston Oilers in return for an All-Pro safety.

Muhammad Ali's shortest poem goes, "Me, Wheeeeeee!" In a me-me time that all-anything players often declare their semi-greatness, we might expect an All-Pro safety to say he's the fierest tackler, leapingest intercenter and (blush) the most generous contributor to the starving masses in India (blush). So why is Ken Houston saying Ken Houston is no good?

Because he believes it.

At 33, in his 11th professional season, he knows the realities of the game. he works unemcumbered by dreams of grandeur.

"The defense is always in trouble," he said. This was after practice at Redskin Park two days ago. He looked up from a plate of ice cream and apple pie. Smiling, he said, "You play in fear."

An All-Pro plays in fear?

"Sure. It's a game of inches. A quarterback puts a pass out there. It goes off a receiver's fingertips. And everybody says. "So what?" Well, a few inches back, he catches the pass nad it's a touchdown that beats you. Playing defense is the worst position there is because every play can cost you the game."

But no one makes All-Pro by being a dud.

"I know, but I make too many mistakes on pass coverage," Houston said. "I always get beat in practice. I tell you. I'm not that good. I have to work. And then every Tuesday - well. Tuesdays are the hardest part of all. That's when we look at the game films."

Houston closed his eyes at the thought.

"On film, you know you teammates are going to be watching. They'll see what you did or didn't do. This is not a very emotional defensive unit, contrary to what some people say. But it has a tremendous amount of pride."

If the Redskins make it into the playoffs Houston and his defensive playmates will be the reasons.

To digress: The offense has been on vacation, averaging fewer than 13 points a game. Perhaps Allen's latest feat of prestidigitation - he put Joe Theismann in a box and then, for the Big Game, reached in there and pulled out (gasp) Billy Kilmer - will produce more points.

"On film, you know your teammates are going [LINE ILLEGIBLE] tions of the offense's pacific nature seem to begin. "I dunno what's wrong, but we're so close to scoring 30 points a game except we keep making these silly little mistakes and . . ." With Kilmer, a demanding leader leader and proven winner, at quarterback, the offense will be more consistent. Those silly mistakes will occur less often because Kilmer's presence inspires confidence the deed will be done some way.

(One thing more: Allen is gambling with this change of quarterbacks. Many people believe Theismann's stronger arm and scrambling feet make him superior to Kilmer now, to say nothing of the future. Those people believe Theismann will become a big winner any day, maybe even today. So if the Redskins fail with Kilmer, Allen will be an easy target.)

Now, back to Ken Houston. Fittingly in this year of defense, the Washington Monday Morning Quarterback Club has named Houston the Outstanding Redskin of 1977. He'll be honored at a luncheon at the Towndown Club on Monday.

And what does Ken Houston think about that?

"Possibly, I was a better player last year," he said with a smile.

Just no good now, huh?

"Well, I was steady this year. I'll say that. I haven't been beat - knock and wood - too frequently, and I'm not doing things to lose ball games."

Houston leads the Redskins in interceptions this year with five. He may lead the world in stunning tackles (a college linebacker. Houston says, "I like a good lick"). He is All-Pro. All Modest.