When last seen in Memorial Stadium, the Baltimore Orioles were standing on their diamond in various stages of emotional undress, waving and blowing kisses to a capacity crowd, some of the players wiping away tears.

That day, in the wake of their season-in-the-balance loss to Milwaukee, the Orioles seemed more revived than disheartened; a team that thought its moment had passed was convinced once more that its destiny lay in the future.

"I can't wait for Opening Day," Rich Dauer said then.

These days, the Orioles are playing in Memorial Stadium again. Or, rather, they are playing baseball under Memorial Stadium.

In a cold, narrow, tunnel that looks like a coal mine shaft or an underground railway between ICBM silos, most of the Orioles have, for the last month, been throwing 90-mph fast balls and hitting 400-foot home runs.

After almost 30 years, the team has its own offseason, indoor facility.

Sort of.

If you don't mind wearing a wool cap and taking batting practice while you watch your breath in the frigid air, then this is spring training north.

If you don't mind gunning the ball back to the pitcher low and hard so your throw doesn't hit girders that hang lower than a living room ceiling, then this spot has all the charm of Miami.

If you don't mind the bad lighting and the mountain of dirt a few feet away that looks like it might turn into an avalanche, and if you don't mind chasing a wild pitch into an uncharted black hole that looks like someplace the Alien would call home, then this is the offseason paradise you've always wanted.

The Orioles love it. You can't keep them out of the place.

Earl Weaver discovered this crypt that stretches for 200 feet through the bowels of the stands from first base to the right-field bleachers. Only entrance: through the backdoor escape exit of the umpires' dressing room. Last winter, the city agreed to bring in earthmovers and clear enough area for one pitcher's mound. That was such a hit that the plows returned and now there are two mounds and one net-enclosed batting cage.

Although the dank tunnel is only a few degrees warmer than the wintry field, more than half the team works out here voluntarily three times a week. Fellows in the big bucks bracket--Jim Palmer, Ken Singleton, Eddie Murray, Mike Flanagan, Scott McGregor and Dennis Martinez--have been regular denizens of this pit since the new year began.

The Orioles like to say they're doing this foolishness in the name of conditioning, getting an edge on foes, rehabilitating injuries. But they know that's mostly nonsense. Anybody who can't get in shape between Feb. 18 and April 5 isn't trying.

They're here for the same reason that fans walk through the snow to buy the Sporting News on Christmas Day. The Orioles can't wait to get back to the game, get back to each other, back to feeling the tools of their trade in their hands.

"Welcome to the catacombs," says Flanagan.

The report of his fast ball striking the catcher's glove sounds like a .45 magnum. "Jeez, Charlie, can't you get that glove to make any noise? It's like throwin' to Grandma. It's depressing," Flanagan agitates his catcher. "I'm gonna blow out my elbow trying to make that glove pop. Take the silencer off that thing, will ya?"

"Bring some caps next time and put 'em in the pocket," snaps Don Stanhouse.

"Let's see, what other pitches do I have?" Flanagan mutters. As he winds up, Ross Grimsley sneaks up and yells, "Swingbatterswingbatter." The pitch bounces 10 feet short of the plate. Oh, to be 13 again, and in the major leagues.

While one pitcher works, others watch, critique and crack wise.

"Turn your body more on that changeup scroogie," a coach tells Flanagan.

"C'est si bon," says Grimsley. "That'll keep 'em from hackin' at everything. Even that guy who starts swinging as soon as he sees you. Who was that?" "(Larry) Milbourne," says Flanagan. "Seven pitches. Seven swings. Seven line drives. Seven outs. I drive him crazy."

Pitchers call out hitters' names, situations from the past. "Brian Downing. Score's 9 to 8. Give him gas on the black," says Stanhouse, recreating his 1979 playoff save.

Stanhouse throws his slider. Everybody snickers; it didn't break enough. "Pow, pow, boom, baboomboom," the mocking voices echo and rumble in the tunnel.

Flanagan cuts his eyes up and to the right like an outfielder watching a home run go over his head. There's laughter for an old team joke. Flanagan once gave up a home run in Yankee Stadium that was so long that the Orioles' bullpen told him that the faces on the center-field plaques of great Yankees like Babe Ruth had all cocked their eyes that way to see where the ball landed.

"Just like my underalls--no wrinkle," says Stanhouse of the pitch. "But, hey, look at it this way, they jam themselves a lot on those sliders that don't break. Catcher yells 'slider,' it just hangs there and spins and you got yourself a double play . . . the art of an aging pitcher. Take a little off, put a little off." The staff snickers at the Unusual One's theories.

"Let's wind this down before I have a heart attack," says Stanhouse. "Only five more workouts before we pack the car for Florida. Gotta break down the adhesions in my driving arm."

In its short history, the tunnel already has its lore. Players say it took so long for it to become reality "because Boog Powell couldn't fit in here." Tippy Martinez won't pitch in the tunnel "because there's no phone for Earl to ring and make him get up seven times." Palmer is the fastest working mole, pitching rapid-fire "so he can fly to New York for an underwear signing and still get back in time to go to bed."

Back in the clubhouse, all the trunks and bags are packed, weeks ahead of time. Golf clubs and fishing poles stand in the corner. The barbs, too, are being sharpened. Trainer Ralph Salvon steps on a scale to prove that he has just lost his 50th pound. To celebrate, he breaks out designer jeans. Players speculate on what brand name they might be; they decide Salvon's jeans are not by Jordache or Calvin Klein, but by Omar. The tent maker.

Do these weird workouts bear any relationship to real baseball?

Flanagan, amidst the kibitzing of his mates, seems puzzled. Don't outsiders realize that baseball is not just a particular setting or time of year? It's a group of peers and a state of mind.

"Everything's here," says Flanagan, grinning, "but the pressure."