The Spaceman was trying his best.

Standing bareheaded in the rain in the deserted right field of Memorial Stadium, Bill Lee, the calculating, endearing eccentric of the Boston Red Sox, was hitting fungos to himself.

Like a child in solitary amusement, Lee had one bat, one glove, three balls and an expanse of unused, if wet, grass.

About 20,000 people were watching and hoping in vain that the Baltimore vs. Boston game would not be rained out. It was.

Lee would smash a ball high in the air, drop the bat, put on his glove and set out in furious pursuit. Once camped under his own fly ball, Lee would try to catch the ball, behind his back - sometimes succeeding, sometimes denting his cranium in the attempt.

Slowly, Rick Dempsey, the unknown but genuine eccentric of the Baltimore Orioles, started his walk from the left-field bullpen toward second base.

The crowd, still giving Lee polite cheers and teasing boos, never noticed Dempsey, although he had towels stuffed under his uniform, his O's cap pulled down almost over his nose, shower clogs on his feet and a bat in his hand.

Lee noticed first. He knows a genuine extraterrestrial when he spots one.

Lee had been in Fenway Park on the final day of last season when Dempsey, during a rain delay, had performed a long, impromptu pantomime that brought a dozen ovations.

Yesterday, Dempsey ceremoniously flipped aside his clogs. Then, bat and hands clasped behind his back, he began skating toward home plate, slidding yards at a time across the slippery tarpaulin in his stocking feet.

"Tap, tap, tap," went Dempsey's bat on the ground as the puckish Bird catcher pretended to search for the sound of home plate under the white tarp.

After introducing himself with a bow to all corners of the park, waving his arms to get the stodgy crowd into the spirit of the thing. Dempsey pointed toward the right-field bleachers a la Babe Ruth, that great Baltimorean.

Two southpaw swingers later - both marvelous imitations of the bandy-legged Babe's whiffs - Dempsey had changed his mind. He pointed to the left-field bleachers, swung mightily and launched the phanton ball.

Dempsey's circuit of the bases had players on both teams craning over each other's shoulders in the dugouts.

At first base, Dempsey tripped over the bag. At second he tried to bury his nose and one of his shoulders under the sack ("I was trying to make a left turn," Dempsey explained later.)

At the hot corner Dempsey's hook slide took him through the coach's box. At home plate, flopping in full sprint on those convenient towels, Dempsey belly-whopped at least a dozen feet, his back arched like that of a delighted seal.

Some of the thousands of fans huddled in the exits gave a scattered cheer, louder than some Memorial Stadium crowds mount in an entire game.

With Dempsey's final slide, this week's stellar Red-Sox-Orioles series came to a fitting ending.

"We had three great one-run games in a row," said the O's Mike Flanagan. "Power on Thursday, pitching on Friday and defense on Saturday.

"I was wondering what we'd do for an encore today. It was Dempsey. He might have been the best of 'em all."

Ironically, Dempsey was the only person bitterly disappointed by his brilliant minutes of mimicry."

These Baltimore people are just dead. They didn't pick up on it at all," said the fiery Dempsey. "I practically had to beg them to get with it. These people are horse meat."

"Was this game televised back to Boston?" Dempsey asked in the amused O's locker room.

Told that it was, Dempsey glowed. "Right on. Boston wants me," he said. "Man. Fenway Park was vibrating last year. They made me come back out to do the Babe Ruth home-run bit. People sent me gifts in the clubhouse." I got stacks of mail back home in California.

"Boston appreciates you going out on a limb to have some fun." Today was terrible, terrible," he said, half kidding, half hurt that Baltimore fans were so blase."

"Maybe Boston fans are better mudders," offered Ken Singleton. "That's just Baltimore," said Mark Belanger. "We know what to expect."

Despite the damp response, the antics of Dempsey and Lee showed baseball at is most playfully charming.

Neither is a gifted player, yet both prosper on qualities that baseball always makes a place for. Lee typifies the briny curve-baller who survives on gall, while Dempsey, according to Boston Manager Don Zimmer, is "the No. 1 hard-nosed guy in this league. I love him. Lotta guys play hard. I think maybe Dempsey plays the hardest."

Moments after Dempsey's belly crossed home plate, at 2:45 p.m., the game was postponed.

Soon after 3, the crowd had gone and the light drizzle had stopped. The tarp was removed so the Birds' hard infield could get needed moisture. As of 6 o'clock not another drop of rain had fallen. The field was dry.

Cynics will say that the Sox and O's had planes to catch. Or that the makeup date - Sept. 6 - might draw 50,000 people, not yesterday's soggy 20,000, if a pennant race still exists then.

They will say the Birds sold extra tickets by waiting until well past game time to cancel. They might even mention all those hot dogs and beers that fans consumed during their long wait."

Play fair and try harder to get the game in, they will say.

However, for those who say George Boomer Scott and Dwight (Dewey) Evans hit their grudge homers Thursday, who saw Flanagan fan 13 Friday and who saw five game-saving defensive plays, Saturday, Lee's flaky fungos and Dempsey's demented base running were as good a curtain call as could be asked.