On a raw, autumn-like night, the Orioles faced a raw truth: unless their pitching staff returns to form soon, Baltimore will be in serious trouble in the American League East.

Mike Flanagan, who had not started since Aug. 23 because of an arm injury, started and lasted less than two innings as the Milwaukee Brewers beat the Orioles, 5-1, tonight.

He gave up three runs, enough to put Milwaukee ahead for good and enough to put the Brewers in first place in the American League East. Pete Vuckovich of the Brewers won his 13th game of the year, but had to leave after five innings because of an abcess on his left leg.

If the loss, which dropped the Orioles to fifth place (1 1/2 games out) was discouraging to the team, so was the loss, however temporary, of Steve Stone. He was scratched as the starter for Sunday's game because when he warmed up this afternoon his arm "didn't have too much life in it," he said.

Jim Palmer, who had been sent temporarily to the bullpen, will get a chance to start again, on Sunday.

When the evening began, the Orioles were one game behind with a chance to move into first place. "Can you believe we're in fifth place and if we win we're in first?" Weaver asked.

They had their chances. They had two on with two out in the fourth and fifth innings and couldn't score. "When you lose like this, it looks like you're not trying," Weaver said. "I've never had a ball club as enthusiastic as these guys are.

"But when you hit into double plays (three, and the Orioles lead the league in that department) and don't get no runs, you don't look too good."

Neither did Flanagan.

With just 15 games remaining, the Orioles need Flanagan, who has been as close as a human being can come to an Iron Mike. Before this injury, Flanagan had made 157 consecutive starts since joining the starting rotation in 1977. The only good thing that could be said about last night was that he felt no pain. "Nothing hurt," he said. "I thought I threw all right." Not hard enough, he added: only 83 mph, according to the radar gun.

In the top of the first, Paul Molitor led off with a single to left and stole second. After Robin Yount popped up, Flanagan walked Cecil Cooper and gave up an RBI single to Ted Simmons and an RBI double to Gorman Thomas. The Brewers led, 2-0, and the Orioles fidgeted.

When Flanagan hit designated hitter Mark Brouhard with the second pitch of the second inning, Weaver yanked him. Brouhard scored on a bloop double off reliever Sammy Stewart that plopped in front of Jim Dwyer in soggy right field.

"If it was June," Weaver said, "you'd probably leave him (Flanagan) out there and get a little work. He hadn't had time to find himself. But in September we ain't got time."

Although Stewart gave up two runs, one in the fifth on singles by Molitor and Cooper and a fielder's choice by Simmons,, and another on Thomas' 20th home run in the eighth, he leads the American League in ERA at 2.06.

"We just haven't hit that comfortable spot," Stewart said. "We're sitting back and letting them handle us instead of being aggressive. For the first time tonight, someone in the dugout yelled, 'Take a bad hop.' It's not that intense on the bench."

And it showed. The game, as General Manager Hank Peters put it, was "a stinker."

In the fourth inning, for example, Dwyer reached on an error but Ken Singleton hit into the Orioles' 94th double play. Eddie Murray, who has 35 RBI in the last 35 games, got an infield hit -- he was four for four and scored the Orioles' only run in the second inning after tripling. John Lowenstein dribbled a ball toward Cooper at first. He dived and made a graceful tag, but forgot to bring the ball along with him.

Two on, two out. Dan Graham popped out to short.

In the fifth, Rich Dauer singled to left and Dwyer walked. But Singleton, who has not had an extra base hit in 20 games, and who fell below .300 for the first time this season, flied out to shallow right. "It isn't just Kenny," Weaver said. "We ain't got enough guys hot."

That it ended this way was somehow fitting. With two out in the ninth, the count on Rick Dempsey went to 3-2. He flailed feebly at an outside pitch for the third strike.

"The people in the stands booed," Weaver said. "It's like he refused to walk."

As everyone knows, you have to walk before you can run.