Circle it on your calenders now -- the last 11 days of the baseball season, Sept. 24 through Oct. 4. Don't take that long-dreamed-of vacation to Europe. Plan on being someplace where you can keep tabs on the New York Yankees and Baltimore Orioles when they meet next time.

As the two teams left Yankee Stadium tonight, all the old heads on both teams knew the meaning of this night's 12-3 New York victory, as well as the cumulative impact of the past 11 days in which these teams have played six times.

What these clubs now know is what they feared all along: neither can get rid of the other. They're both just too good.

"We crushed 'em tonight," said Reggie Jackson, who was on the bench as his Yankees had completed a dramatic, ovation-filled three-game sweep with a 17-hit offense, plus eight innings of one-hit shutout pitching by 20-year-old rookie Gene Nelson. "And do you know what it all means? It don't mean a damn thing. All it proves is that they did to us at their place last week.

"These teams are so close that only one thing's for certain. The next time we meet (seven times in those final 11 days) it's going to be for the cash," said Jackson after the Yankees had moved within .004 of the Birds' precarious first-place perch.

That's the long-term view, and almost certainly the correct one. That's why Manager Earl Weaver was in the chipper mood that he always saves for meaningless catastrophes. "Ain't baseball a wonderful game?" he said, finding amusement, as always, in confounding expectations. "We got a nice little race now. We might have gotten too big for our britches if we'd had a little luck and won the first two games here. This'll remind us who we're up against. As long as we're ahead, everything's coming up roses."

Now that the philosophers of pennant races past -- Messrs. Jackson and Weaver -- have issued their profundities, let's go back and relish the short-term feast that so thrilled the 37,954 here.

Make no mistake, the Birds were shot, stuffed and mounted this evening for the viewing pleasure of George Steinbrenner by those ruthless taxidermists in the pinstripes called the Yankees.

The Yankees led, 11-0, after six innings, blasting emergency Oriole starter Dave Ford for seven runs in fewer than four innings. After O's leadoff man Al Bumbry singled to open the first (then left for a pinch-runner because of his still-injured thigh), the Birds did not get another hit off the speed-changing Nelson until the ninth, when Rich Dauer and Eddie Murray homered and Terry Crowley doubled to prevent the rightly from getting his complete game.

This was a night, just like the first O's-Yanks game in Baltimore last Tuesday when the Birds won, 10-1, when the crowd spent most of the night bestowing ovations. Bobby Murcer got one for his 1,000th career RBI. Dave Revering, who ignited this sweep with his 11th-inning homer Tuesday, got one for another homer, this time to right. And, above all Nelson got one for matching his fellow rookie Dave Righetti, who also shut out the Birds for eight innings the night before. "I felt just like you'd think I'd feel," beamed Nelson. "You get something running up and down you like a chill."

Was it just 11 days ago that Mark Belanger was being called out for a double ovation in Baltimore for a long home run?

Symmetry is one thing, but this was ridiculous.

Last week, the Yanks left Baltimore after losing two brilliantly close games, plus one embarrassing slugfest. They returned to New York in a swirl of internal dissension. Now, the roles are reversed. The Birds have lost two brilliant tense games -- both won by Yankee homers in the 11th inning. And they have been humiliated in a slugfest. In all six games, the Yankees outscored the Orioles, 29-28 -- all of one run.

The Birds now head to the West Coast with a five-game losing streak (their longest of the year) and a team batting average under .180 in those games. The Yanks have now won six of seven games. Perhaps the richest irony is that, to a degree, the clubs have even temporarily exchanged personalities. It's the Orioles who are making Yankeelike remarks about each other.

Before this game, it was Jim Palmer and Doug DeCinces sniping at each other like the best of Bronx Bickerers. Their occasional animosities have a long history. Among all the Orioles, they are the two fondest of the TV limelight, the two most likely to use the word "I," the two most often injured, the two most often in search of sympathy for playing hurt, and the only two who have ever asked to be taken out of games because of injuries which teammates (and Weaver) viewed with skepticism. They are, in fact, very much alike: intelligent, glamorously handsome, hypersensitive to criticism and prone to complaining.

That's why there was suppressed twitters among the Birds when DeCinces on Wednesday night said, "This is a team with 24 players and one prima donna." He meant Palmer, but the same quote might be applied with a bit of justice to him. The pair's latest hard feelings centered on a ground ball that endangered DeCinces' profile on Saturday and which the third baseman successfully avoided with the matador "ole" pivot that he has perfected on smashes directly at him. Palmer took himself out of the game before the next inning and has had a "stiff neck" (an appropriate injury) ever since. He was scheduled to pitch tonight, but scratched himself Wednesday.

Perhaps Palmer had looked in a crystal ball and seen what would happen to DeCinces this evening. With two out and two on in the Yankee second, Bucky Dent hit just the sort of hard two-hopper directly at DeCinces has petrifies the hot cornerman, who had gotten four broken bones and a lifetime's worth of back problems from just such balls that have taken vicious hops. DeCinces has excellent range, but he sees bad hops at the face in his dreams and plays that way. This grounder ate him alive for an error as DeCinces kicked the ball halfway to second base. That opened the floodgates for four unearned, two-out runs. Just for spice, the next Yank hit a chop on which DeCinces slightly mistimed his jump and missed by an inch or two.

After this debacle, the Orioles suffered one final indignity. Originally, this game was scheduled for 2 p.m. However, when Yankee owner George Steinbrenner learned that the Birds had to fly to California for a game in Anaheim on Friday night, he exercised his prerogative to change this game to night, forcing the Orioles to fly all night, then play red-eyed.

After these three nights, it could be a long flight.