For weeks the Boston Red Sox have been falling, like a sky diver whose parachute will not open.

In the last three days, the Sox have been plummeting at such a terrifyingly rapid pace that they have been too close to unconsciousness to yank at the rip cord.

Yesterday the Rex Sox landed with a colossal, sickening S-P-L-A-T in Fenway Park. What had looked like the earth rushing up at them turned out to be the New York Yankees.

The final score of this Yankee victory was only 7-4, not nearly as brutal as the previous numbers in this Fenway funeral as Fenway funeral: 15-3, 13-2 and 7-0.

However, this week was the unkindest defeat of all, since it destroyed the last of this Olde Town's illusions.

The Boston league lead, once 14 games, is now nothing.

The Red Sox and Yankees are tied for the best record in baseball - but anyone who witnessed this series knows the New Yorkers own the psychological advantage.

The Bronx world champions smoked 18 hits yesterday, all singles, and sent 26 runners scampering round the sacks.

The Yanks outscored Boston, 42-9, in this four-game sweep, and outhit them, 67-21. The Sox tossed in a dozen errors.

The Sox and Bombers each had 11 extra-base hits, but the Yanks had an incredible 56 singles. In the end, the Bosox body was not bludgeoned to death in normal Fenway fashion, but was killed with tiny darts - a water torture of singles.

Once again, the Yanks felt that the quickest execution was best, jumping to a 6-0 lead as they earlier margins of 12-0, 13-0 and 7-0.

The Sox were left without a thread of dignity. Their rookie starting pitcher, Bobby Sprowl, looked petrified and lasted one-third of an inning.

The Boston bullpen hero, Bob Stanley, the 13-2 vulture, replaced Sprowl. His first pitch resulted in a two-run single. In three innings, he was tatooed for 10 hits.

The Yankee relief ace, Rich (Goose) Gossage, showed the Vulture how, mopping up Ed Figuerosa's win with three menacing innings.

"In 37 years this is the worst performance I've ever seen," said Sox Coach John Pesky. "If feels horrible."

"Right now, we're tied with them, but they're a better club man-for-man," said Red Sox shortstop Rick Burleson. "The season starts all over again tomorrow, but they have the advantages - health, momentum, confidence . . .

"They're a money ball club. Are we?" Burleson asked. "If we're going to do anything but die, we've got to kick ourselves in the butt.

"We've got guys hurt. But (New York's Thurman) Munson got beaned in the first game and he's played dizzy and he hasn't made a mistake. Their cleanup hitter (Reggie Jackson) got out of traction in a hospital bed to get here."

While Boston has lost nine of 11, with 26 errors, New York has won 16 of 18.

"It's a pity," said New York's Paul Blair, "that if we win, people will say, 'Boston choked,' not "The Yanks put on a great drive to win.'"

Both observations have their rightful place in any account of this carnage.

Seven of the Yankee hits yesterday were tainted.

Roy White alone had three hits that bounced out of Burleson's glove - one bloop, one chop, one grounder. Fred Lynn and Gary Hancock both misjudged filies into hits that led to runs.

Stanley had two beauts. Once, he fielded a bunt and twisted his ankle simultaneously. Result: no throw. And once he napped while George Scott made a phenomenal diving stop. Result: no one covered first.

The Yanks tried to help. They left a dozen men in scoring position, grounded into three double plays, had two men gunned down foolishly at the plate and had a runner thrown out stealing.

But each Yankee malfeasaneo, however, was overcome by a subsequent hail of line drives. Lou Piniella finished the series with 10 hits, while Munson and Williw Randolph had eigh apiece. Randolph reached base 16 times.

While Scott, Burleson, Carlton Fisk (two thieves thrown out in last 21 attempts), Butch Hobson and a collection of right fielders tied for the distinction as Least Valuable Boston Defender, Graig Nettles wast he Yank defensive star.

"He stole 10 hits from us in four games," Burleson Md. "Nettles is a magician," Pesky said. Pesky said. "One of the best in history, and by far the best today."

If all Yanks earned praise, then no Sox escaped blame - certainly not Manager Don Zimmer. "If I start Sprowl and he loses," Zimmer said before the game, "my throat's cut again."

The Sox had not been swept here by the Yanks since 1943. The Bosox were 52-17 in this jewel-box ballyard until this weekend.

A year ago June, the Red Sox staged their Boston Massacre - 16 homers in three games to bury the Yanks. The total score in that specatcle was only 30-9 for Boston, not 42-9.

"Emotion," Fisk said. "It practically drips off the ball in this rivalry. There's nothing like it.It's like a giant Will directs the whole game and one team or the other has complete control.

And the other just keeps falling . . . falling.