Dan Quisenberry is the best performer in baseball.

This is a painful conclusion. After all, the only thing lower than Quisenberry's earned run average (1.65) is his charisma quotient (0.00).

But, fair is fair. The record book is unequivocal. For the time being, we're stuck with Quiz as baseball's main man.

Few have noticed that the Kansas City Royals reliever is two-thirds of the way through one of the greatest pitching seasons in the last 50 years.

He has been the best relief pitcher in baseball thus far in the 1980s and, at this moment, is having the greatest bullpen season in history. And he's doing it with almost everything against him.

Quisenberry, known more for his humor than his heroism, is working on a landmark baseball season that outshines the importance of the Chase of '82--Rickey Henderson's 130 stolen bases.

No pitcher has ever had 50 wins-plus-saves in a season.

The record is 48 by John Hiller in his once-in-a-lifetime season of 1973. In fact, Hiller's the only man who has ever had more than 45 wins-plus-saves. At his current pace, Quisenberry would have 52 wins-plus-saves.

Should Quiz's Quest for 50 be successful, it should be considered the equivalent of a starter winning 30 games.

Just as incredible as Quisenberry's current mark of 31 saves and five wins (36 wins-plus-saves) after 112 Royal games, is the fact he only has one loss. At his present pace, Quisenberry would have 51 wins-plus-saves-minus-losses.

The all-time record in this W+S-L area is 43 (by Hiller), and he's the only reliever ever to reach 40 in this bedrock measure of excellence.

If Quisenberry achieves such a "plus" factor of 50 in one season, it's a pitching mark that may last as long as Joe DiMaggio's 56-game hitting streak.

By the way, Quisenberry needs only eight more saves to break Hiller's all-time record of 38.

Let's make this simple for the novice.

So far this season, Quisenberry has stood on the mound and greeted his catcher after the final out of 34 Kansas City victories in which he's been the winner or the saver. He's also finished up a couple of one-sided Kansas City wins, but he wouldn't even want credit for them. Every one of those 36 successes has been, by definition, a close game.

On the other hand, in all those tight battles, Quisenberry has lost once.

So, he's "plus" 35 already this year.

For comparison, when Mike Marshall pitched in 106 games in 1974, he had 36 wins-plus-saves, and a dozen losses. His "plus" for the whole season was 24.

When Elroy Face was 18-1 in '59, he was only plus 27. The great Rich (Goose) Gossage has never had a season of 40 wins-plus-saves.

Because superstar relief pitchers are essentially a development of the last 30 years, baseball--seldom quick on the uptake--barely has any idea how to evaluate these men who are now at the very center of the sport, assuming a place of importance equal to the greatest sluggers or starting pitchers.

The W+S and W+S-L stats are probably the best measure of a reliever's quality and durability. And Quisenberry is rewriting the record book in these areas.

Some may feel Quisenberry's stats this year are a fluke. After all, Hiller's performance in '73, when he had a 1.44 ERA, was the only great season of his career; Hiller never had more than 15 saves in any other year.

That's not the case with Quiz.

If all the great relief pitchers in history were asked to present their three best seasons for inspection, Quiz would get an A-plus on the test.

Assuming that Quisenberry finishes '83 decently, no reliever in history can match the three super seasons he's already had in the '80s.

In '80, Quiz had 45 wins-plus-saves and last season he had 44.

By the end of this season, Quisenberry will have had three of the top 10 W+S seasons in history. And all have come within a span of four years. In that "other" season--the strike-shortened year of '81--Quisenberry had a 1.74 ERA.

For a pro athlete, Quisenberry is skinny and awkward, a poor fielder. He looks like your funny, friendly junior high school civics teacher. Lord knows what he'd do at bat. In a sense, it's hard to say he's an athlete at all. He's more a craftsman, a self-disciplinarian and an innovator. How else would you describe a man who teaches himself to throw underhanded, then, after he's already a star, adds a submarine knuckleball to his repertoire?

Quisenberry, who ruminated in the minors for five years, loves to say things like, "I've seen the future and it's much like the present, only longer," and, "The best thing about baseball is there's no homework."

Yet, looked at from the proper perspective, Quisenberry's accomplishments are even greater than they appear. He has the best control in baseball: 10 walks (some of them intentional) in 103 innings. He's also the hardest man in baseball to hit a homer against--allowing only three in 49 games. Of big-swinging Reggie Jackson, who can't get the ball out of the infield against his sinkerball, Quisenberry once said, "Reggie hit one off me that's still trying to burrow its way to Los Angeles."

For a reliever, he's a workhorse. This year, he will pitch 140 to 150 innings in 70 to 75 games--the same heavy schedule he thrived on in '80 and '82 (264 innings in 147 games).

Quisenberry has done all this despite playing in the worst imaginable ballpark for a pitcher who lives by the ground ball--Royals Stadium with its lightning turf. Put Quisenberry in any one of a dozen fairly large grass parks and his career ERA, which is around 2.50, might be nearer 2.00.

As a final twist, Quisenberry is going after 50 wins-plus-saves with a mediocre team around him. The Royals are 55-57. Thus, he has won or saved 65 percent of the Royals victories. Quisenberry has gotten a win or save in 35 of the 38 "save situations" he's been handed.

If you were starting a team today and wanted to pick the single most vital player for your club, both for the present and for the next few years, Dan Quisenberry--30 years old and four prime seasons into his quest to be the greatest relief pitcher in history--would be the wisest choice.