The Baltimore Orioles have stumped the panel again. But this time even Groucho Marx probably wouldn't laugh.

For 25 years, the Orioles won more games than anybody, although, to tell the truth, no one knew for certain how. Now, after 100 games, the Orioles are mysterious once more. How can they be so lousy?

This team has three former 20-game winners, plus a former American League leader in victories. All are in their prime and in good health. Also, they have a 23-year-old with fabulous stuff and a .600 career record. All five have World Series experience. Both radar guns and human eyes agree that, as a group, the five have never thrown better at the same time.

This club also has the first five-deep bullpen in franchise history, led by a million-dollar free agent with a sub-2.50 ERA for the last six weeks. Manager Earl Weaver has never been able to phone so many strong arms.

As if this weren't enough, these Orioles also have the best-hitting club in Baltimore history. Their Nos. 3-4 hitters will probably both end up in the Hall of Fame and, together, are on a 240-RBI pace this year. Their No. 5 hitter is a nine-time All-Star on a 28-homer, 86-RBI pace.

The top of their batting order begins with a solid .265 hitter who steals 65 to 70 bases a year and a swift No. 2 hitter batting his usual .320.

The rest of the batting order oozes power. The Nos. 6-7-8 slots are occupied by a half-dozen platoon players who have combined for 48 homers and 142 RBI in less than 1,000 at-bats. At that rate, they'll average 26 homers and 77 RBI per batting order slot for the year, with a solid .260 average.

Nobody in baseball approaches such consistent punch so low in the order. Even the No. 9 hitter, Rick Dempsey, is having a .250, 10-homer, 50-RBI year.

As for the bench, it's as good and versatile as any "deep depth" Baltimore teams. Rich Dauer brings a glove to second and third base. Al Pardo is a fine backup catcher and prospect for the future. John Shelby can switch hit, pinch run and chase flies excellently.

As for defense, Baltimore may never have had a better outfield, and catcher, first base and shortstop all have fellows of near Gold Glove ability. With quick sure-handed Floyd Rayford now at third base, even the weakest defensive link (Alan Wiggins at second base) is adequate.

The team will be in perfect health when rookie reliever Nate Snell (2.12 ERA) returns next week. Add to this a Hall of Fame manager, a top general manager in Hank Peters and one of the smartest and most open-walleted owners in baseball in Edward Bennett Williams.

In sum, the Orioles have power, speed, clutch hitters, experience, youth, defense, five starters any club should envy, a bullpen of better-than-average potential and as much management brainpower as can be found.

Taken together, the club is hard-working, yet usually relaxed and, in good times, fairly funny.

So, how come the Orioles are in fifth place, 12 1/2 games out of first? How come a dozen players now hide after losses, while others pick and choose their spots to talk to the press, like classic love-me-when-I'm-hot-but-forgive-me-when-I'm-not prima donnas?

"I don't know what's left to say," says Peters. "The problem this season has all been the pitching (4.40 ERA). It's strange. We don't have the answer. You find yourself saying, 'What in the world is going on?'

"I heard about a team once that hired a witch doctor. Maybe it's time.

"Storm Davis and Dennis Martinez have had particularly bad years and it's not like they're rookies or unproven or hurt or old. That only compounds the mystery . . . They have their personal problems, like we all do. But you have to find a way not to take that on the field with you."

The players themselves seem dazed. "Give us a break," snaps Scott McGregor, usually the most placid soul. "It's one of those years."

"We used to anticipate the good things that would happen," says Sammy Stewart. "Now we're looking for the bad."

"On paper, this is the best team I've ever been on," says Cal Ripken Jr., including the '83 world champions. "All year the little things haven't gone our way. You end up trying too hard. It's just not the same confident feeling."

Since 1984, when the Orioles won 85 and weren't too shabby, the team has added free agents Fred Lynn, Lee Lacy and Don Aase, plus the expensive Wiggins. Rookies Larry Sheets, Snell, Ken Dixon and Pardo have all worked out as well or better than hoped. Rayford (.328) has been a shock, except to Weaver, who's always loved him. Even Mike Flanagan has returned from his Achilles' heel injury with something like his old 1979 form.

All this is what drives the Orioles nuts. They don't think they should be good. That would make their 51-49 record infuriating enough. They think they should be great.

"Believe me," says coach Terry Crowley, "this is a hard-working team, a loose team and a team that believed it could win the pennant."

The most deeply troubled and confused Oriole is Weaver, who, above everything, prides himself on his "baseball judgment." The last seven weeks have just about shorted out the control panel on his cerebral cortex. The man came out of retirement to join a nightmare in progress.

"We gotta stop talkin' about how good we are and start showin' people how good we are," he sputters angrily.

"I ain't gonna say, 'Play for second place.' I've never been involved in that until maybe the last week of the season and I'm not gonna start now . . . I just want us to make up enough ground so it's fun again.

"Let me make one thing clear. I'm happy doin' this. I just feel terrible bad for Mr. Williams. The man thought I could do something and I haven't done it yet. I say 'yet.' "

Since the '83 World Series, an aging Oriole team has been rebuilt at huge expense. Now, strange as it sounds, the job is basically complete. The new Orioles either will reclaim their position near the top of the game, and do it with a vengeance, or they may suffer one of the worst team nervous breakdowns of their generation.

The Orioles have undergone a personality, as well as a personnel, transformation. That new team character, or lack of it, isn't finally forged yet. The fires of defeat are determining its outlines now. You learn more truth about people in bad times.

This is a club that, before too long, will either explode or implode.

"I believe," says coach Frank Robinson, "that when this finally turns around, we will truly kick some butt."