Thus far, the World Series, which took a well-deserved rest yesterday, has both fulfilled expectations and exceeded them.

Virtually everything fans of the Baltimore Orioles and Pittsburgh Pirates might have expected from their teams, yet almost dared not hope for, has come to pass.

When these orange and black birds and gold and black Bucs meet in Memorial Stadium Tuesday at 8:30 p.m. in the sixth game, it will be vastly different than when they first collided last week.

In just five consecutive games, with no time off to catch their breaths, these teams have amassed a season's worth of knowledge about each other -- impressions they never will forget.

Each team has had 24 hours to perform an autopsy on those first five games in which Baltimore took a 3-2 lead.

"Even the best scouting reports don't tell you much," said O's Manager Earl Weaver. "You want to see for yourself."

What the Birds and Bucs have seen is, strangely enough, exactly what fans in Baltimore and Pittsburgh watched for six months. That is indeed an October rarity.

Too often, World Series baseball bears only a pale resemblance to the brand played all summer. Fingers freeze, bats become heavy, managers get cautious and every pitcher becomes Walter Johnson.

For once, this Series -- despite its

abominable weather -- has brought out the brash gambling best in both clubs, while also revealing the worst secrets each club had hoped to keep in its baseball closet.

First, the good news.

Baltimore, haven of hurlers, could hardly have expected two more galvanizing performances than those of southpaws Mike Flanagan and Scott McGregor, whose complete-game wins must have sent an electric shock of confidence through the Orioles.

That current of energy -- "pitching is the key to team confidence," says Weaver -- may have given Baltimore the charge to steal the vital, and perhaps pivotal, fourth game from Pittsburgh.

No Oriole fan, not the craziest burnout in Section 34, could have wished for a finer example of tight-knit Oriole interdependence than their six-run eighth inning for a 9-6 comeback.

That six-run explosion, with Kent Tekulve on the mound for all six RBI, probably has been the only truly telling blow struck so far -- the only happening that has exceeded the winning team's best reasonable hopes and given the losers a taste of something more bitter than they ever dreamed they would be asked to swallow.

That was the "bonus" victory. The Orioles will have to commit some faux pas of the first order to balance the psychological scales.

The key to the Orioles' hard-to-grasp strength, is, for the umpteenth time, their depth. Perhaps no team since the 1950s-early 1960s New York Yankees -- with names like Cerv, Siebern, Lopez, Kubek, Slaughter, Carey, Howard, Blanchard, Tresh in either platoon or bench roles -- has had such functional and confident players who were in the bottom half of the team in fame and status.

It is the least-known of the Orioles who have done most -- the lineup that one columnist said was as anonymous as a motel register.

Kiko Garcia leads this Series in runs produced -- 10. Bennie Ayala, who awoke the troubled Birds from a 3-0 sleep in the third game, may have struck Baltimore's most-needed hit with his two-run homer to deep center.

"Hey, what are you two stars doing in here?" asked Lee May, man of 344 homers, when he saw John Lowenstein and Terry Crowley taking batting practice with the subs on Sunday after their game-turning pinch-hit doubles of Saturday.

"This group is strictly for '. . . and others,'" said May, who terms himself "temporarily unemployed" because of the no-DH rule.

It is the Orioles' cast of And Others which has them ahead in this Series. It certainly is not their nucleus of supposed stars: Doug DeCinces (.176), Al Bumbry (.176), Gary Roenicke (.167), Eddie Murray (.222) and Ken Singleton (three runs produced).

Perhaps the best concealed strength in this Series has been the overall Oriole pitching staff -- the crew that has allowed the Pirates their astronomical .339 team batting average.

How have Baltimore's pitchers kept their team in control of this Series from the outset?

Perhaps pitchers cannot keep a great hitting club like Pittsburgh from doing damage, but they can prevent cheap runs. How? By minimizing walks, allowing singles but not home runs, and by working hard to prevent stolen bases.

In this Series, the Pittsburghers have drawn only six unintentional walks to 20 for Baltimore. The Bucs have just two homers -- both by Willie Stargell and both with the bases empty. And the Pirates still have not stolen a base, while the O's have two.

What is the net result? Despite the spectacular Pirate averages, when every aggregate offensive base is added up (total bases, plus walks, steals and hit by pitches) the Pirates have just four more bases.

When we note that Pittsburgh has made three more errors, we can understand how a team batting .251 can outscore one that is hitting .339, if only by one run, 25-24. In other words, Pittsburgh has not yet closed the fundamentals gap.

The Pirates, for their part, have an abundance of good news -- at least by the standards of a team that is on the edge of a cliff.

Several pitchers on the staff have been effective against the O's in one game or another -- Jim Bibby, Bert Blyleven, Grant Jackson, Don Robinson, Jim Rooker and Tekulve.

What is important is the number of them. The Pirate staff is an absolute shambles with Rooker an emergency starter in the fifth game and John Candelaria (with his injured rib cage) in the same category for his start on Tuesday. No Buc even wants to think about a seventh-game hurler.

But who cares? With just one or two days left before a four-month vacation any pitcher with an ounce of heart can work an inning or two. Pittsburgh's bullpen may look like a bucket brigade from here on in, while the Orioles' perfectly rested staff will work with patrician calm and dignity. tBut in such a short span, how great is that differencce, really?

In fact, Earl Weaver may be tempted to employ midseason standards and go with a strong-looking Jim Palmer or Scott McGregor longer than he should. In October, a no-tomorrow flood of relievers often works best.

The other side of the strategic coin is that both these clubs have exposed their worst weaknesses to each other. Neither of these teams has chinkless suits of armor like the '75 Cincinnati Reds. They can be beaten. In fact, both probably have it in them to self-destruct -- given the proper set of adverse circumstances.

The Pirates like to say, as they did after Sunday's victory, that their blunder-free games are the real them and that their games of pure comedy and boneheaded play are some illusion. Nonsense. There are no "real" Pirates. Their chemistry changes from day to day.

Like any team that brags and swaggers, depends on team charisma and intimidation, they play on emotional jags. The Pirates can lick you silly, or they can put their tails between their legs and quit. They have done both in this Series.

Perhaps Dave Parker is the perfect symbol of the Pirates. He is hitting .429, has thrown out a vital runner at the plate and has made a great run-saving outfield catch in a close game.

He also has been picked off base, dropped a laughably easy fly ball and opened up a huge Baltimore inning by playing a catchable bloop into an untouched single. Parker has no homers and a creditable, but modest, five runs produced.

As for the Orioles, they still do not have a team leader, a single source of on-field stability to complement the tactical ballast given by Weaver. In other words, they have no Stargell.

The Orioles have fulfilled their roles as well, supported each other in such 25-for-one spirit all year, that they never faced a true back-to-the-wall game. Is the seventh game of a Series the place where Hall of Famers traditionally step forward? Or will Terry Crowley do? We may yet find out.

Finally, as might be expected, both Families in this Series are having their squabbles. In a way, it is humanizing after all the incessant talk about brotherhood.

O's catcher Rick Dempsey, while discussing why he does not catch Dennis Martinez, wandered from the subject, then said, "You know, on every team you have 23 professionals and two idiots."

Dempsey may not have meant Martinez. Or, jokingly, he may have meant both Martinez and himself. But it did no good for the quote to make a national wire service.

Rich Dauer has made it no secret that his feelings have been ruffled by sitting on the bench in five postseason games while Billy Smith, whom he thought he had beaten out conclusively years ago, was in the lineup. Dauer has taken batting practice left-handed and said, "I have nothing to say . . . for now."

On the Pirate ship, Bruce Kison who is playing out his option, is not Mr. Popularity. After getting knocked out in a third of an inning of the opener, Kison, a life-long "cold-weather pitcher," has said that he isn't sure he should pitch in such cold weather for fear of hurting his arm further.

Or, the Pirates would like to know, is it for fear of hurting his arm, devaluing himself in the free-agent sweepstakes, and losing a huge contract with another team in just a few weeks?

Now is the hour for tempers to flare, arms to ache, heroes to come forward. The Orioles and Pirates have put on a first-rate long-running show. The curtain rises now on the last set of the last performance. If the finish is worthy of the start, a standing ovation will soon be in order.