The Baltimore Orioles have won every other way in this pixilated season, so it came as no surprise to anyone, except perhaps dumbfounded Manager Earl Weaver, that today they won by mistake.

On the surface, the Birds' 3-2 victory over the Boston Red Sox was a simple affair -- a mixture of Oriole persistence and that age-old Boston will to lose.

Mike Flanagan won his 21st game on a day when he left his best stuff home in Manchester, N.H. The southpaw had 40 relatives in the stands and seemingly as many runners on base around him in his 7 1/3 innings.

Three O's relievers -- Tim Stoddard, Tippy Martinez and Don Stanhouse -- then pitched the last five outs to preserve the Birds' second low-scoring, one-run triumph here in two days.

The Orioles got a four-to-four day with a run batted in from Ken Singleton, the hammer who usually supports Flanagan's arm. Young Gary Roenicke broke a 1-1 tie by doubling off the wall in the sixth off loser Dennis Eckersley. And Eddie Murray drove in the ultimate game-winning run with a checked-swing liner in the eighth.

In all, it was a thoroughly predicatble Oriole day with superb pitching and timely hitting -- spiecd with luck.

Of course, the Red Sox helped, too. Dwight Evans killed two rallies against Flanagan by getting picked off first base and third base.

And Sox third baseman Butch Hobson threw a ball into the Boston dugout to set up one O's run.

The hidden kernel of this game, however, came with one out in the bottom of the eighth when Rick Burleson kayoed the struggling Flanagan with a solo homer into the screen to cut the Bird lead 3-2.

Weaver trudged to the mound and began discussing with catcher Rick Dempsey how Stanhouse was going to pitch to the next hitter.

"Stanhouse?" asked Dempsey, looking toward the bullpen where the 6-foot-7, 250-pound Stoddard was walking into the game. "You better look again, Earl. The guy who's comin' in is awful . . . big."

As Stoddard, who has been inactive for 48 days, reached the mound, Weaver greeted him with words perhaps unique in the game's history.

"I didn't want you to warm up. I don't want you now. But you're too big to send back."

The Orioles had been semiwise to Weaver's mistake since he accidentally said, "Get Stoddard warm," when he meant Stanhouse.

"I see old Stodhouse is warming up," said Sammy Stewart mischievously in the dugout.

Weaver allowed Stoddard to pitch in one man -- Tom Poquette, who filed out -- then brought in Martinez to strike out Fred Lynn to end the eighth. When Weaver finally brought Stanhouse in to begin the ninth, he had used four pitchers to face four Boston batters.

The crowd thought Weaver was simply showing off his pitching. Actually, he was showing off his notoriously poor memory for names.

As Weaver and Flanagan watched Stanhouse give up a one-out double to Carlton Fisk in the ninth, then retire Carl Yastrzemski on a fly and Hobson on a ground out, the manager turned to his Cy Young candidate and, shaking his head, said, "That just goes to show you. We can't do nothin' wrong this year."

"It couldn't have worked out better," said Weaver afterward. "Maybe Ray Miller planned it that way."

True, Miller, the pitching coach has been nagging Weaver to get Stoddard in a game for a week since he was reactivated after an arm injury. And, true, Miller, was heard telling Stoddard, "Stick with me, Big Foot. I'll get ya in there."

Miller insisted, however, that "I have an ear witness. Earl distinctly said, 'Stoddard.'" And Miller didn't correct him.

As the O's, who have won 14 of 18 while Boston has lost 15 of 20, piled aboard their bus in the crisp New England afternoon, they were planning a full-scale in-house investigation and formal trial for Weaver.

Many a Bird was found guilty today. "That was a real ugly hit, Eddie," Mark Belanger told Murray. "That's the worst looking game-winning hit of the week in baseball."

"Way to go, junk ball," said Stanhouse to the flame-throwing Stoddard."We thought you were too big to sneak in there."

For teams with a double-digit lead, baseball is a lark. Today Flanagan won with the sort of nonexistent stuff that has led him to seven quick kayos this year in which he has gotten 37 outs (13 1/2 innings) and allowed 37 runs.

"I could have been gone early again today," said the 21-7 lefty who is 52-24 since June, 1977. "My change up saved me. It's made me a decent pitcher on bad days."

Actually, the Birds had another obscure key to victory. Weaver knew that Billy Smith owned Eckersley. Smith hit four ropes, two of them singles to lead off the sixth and eighth. Each time, Singleton followed with a hit and Smith eventually scored.

The only disappointment in the O's sixth straight win was that Flanagan could not give Yastrzemski his 3000th hit.

"I grew up skipping school to come see Yaz play," said Flanagan. "I used to use his batting stance as a kid. We'd listen to the Sox games on the radio while we were playing our own.

"It would have been an honor to give up his 3,000th hit. I was hoping we'd have a big lead to that . . . well . . . hummmm."

Instead, Flanagan went to those nasty sidearm curves and blanked Yastrzemski three times in his 0-for-4 day.

Now Yastrzemski will try for his two needed hits on Sunday against the O's Steve Stone. "Does that mean he's just a Stone's throw away from 3,000?" asked Flanagan.