Ken Singleton's 16th home run of the season highlighted Baltimore's 4-3 squeak past the Cleveland Indians tonight for the Orioles' 11th one-run victory in the month of June.

The Birds won their 12th in their last 13 games and 17th in 19 thanks largely to 11 walks issued by Cleveland starter Len Barker and reliever Dan Spillner. The badly slumping visitors dropped their ninth in a row.

Oriole starter Mike Flanagan took his ninth success against five losses, striking out eight and walking five in seven-plus innings. He then yielded the hurling chores to Don Stanhouse, of the talented bullpen that has a cumulative 9-0 mark with six saves since May 28.

A Memorial Stadium throng of 18,171 watched. The Orioles moved 144,128 over last year's home attendance at a similar 32-game mark.

"The fans are amazing," Flanagan said, "We were drained mentally from our weekend series but the crowds have helped us keep our drive thus far."

As has been the habit of Oriole opponents this month, Cleveland got on the board first: Toby Harrah, the second batter of the first inning, jumped on a 3-1 pitch for a homer into the left-field bleachers.

Indian right fielder Bobby Bonds, who dropped a fly ball Baltimore two runs in Monday's 3-2 Bird victory, again sprouted goat's horns last night. In the bottom of the fourth, Indian starting pitcher Len Barker loaded the bases with consecutive one-out walks to Doug DeCinces, Lee May and Gary Roenicke.

Then second-baseman Rich Dauer lofted an 0-1 pitch toward the right-field corner. Bonds came galloping toward the wall - and apparently came too close to the unyielding wood for his liking. He momentarily took his eyes off the ball, allowing it to drop unmolested, and DeCinces and May scored. Roenicke then came across on Rick Dempsey's infield out for a 3-1 Bird Lead.

The Indians cut the lead to 3-2 in the top of the fifth after a shaky Flanagan walked two of the first three batters and Rick Manning socked a run-scoring single.

Singleton's 315-foot homer in the seventh gave Baltimore the eventual margin of victory. But before the Birds could claim victory No. 49, they had to sweat through a two-inning relief stint by Stanhouse, whose nicknamed is "What, Me Worry?"

Oriole Manager Earl Weaver, who had said that between every pitch the reliever throws he (Weaver) has both time and cause to smoke a cigarette, probably went through a pack last night.

Flanagan was removed after Manning led off the eighth inning with Cleveland's fifth hit.

"If Mike had still been getting his curve over, I would have left hime in," Weaver said. "But the bullpen's been outstanding ever since the series in Milwaukee (mid-April). Stanhouse, as shaky as he is, hasn't given anything up this year."

Stanhouse (6-1) earned his eighth save and second in two nights.

But first he gave up a single to Andre Thornton that ricocheted off the left-field wall. Cliff Johnson reached base on a fielder's choice, scoring Manning from third, to make it 4-3. Horace Speed, pinch running for Johnson, stole second and next reached third on an infield out. Stanhouse walked Mike Hargrave but retired pinch hitter Jim Norris.

"I've been in the game eight or nine days in a row," Stanhouse said. "It's always fun. Today, I'm the king of the hill; tomorrow, you never know.

"Earl asked me if I'd make it easy on him for a change. Then the first thing I do is let Thornton hit it off the wall. Weaver probably left the game at that point."

Actually, the Oriole mentor hung around to watch Stanhouse retire the side in order in the ninth, getting Bonds (.307) out swinging - the right fielder's third whiff of the contest. CAPTION: Picture, Rich Dauer