Like a badly beaten fighter, the Boston Red Sox are barely hanging onto the ropes.

And the Oakland Athletics are waiting to apply the knockout punch today in Game 4 of the American League playoffs."It's not over; we still have another game to play," Boston catcher Tony Pena said Tuesday after the A's extended their domination of the Red Sox with a 4-1 victory.

Pena spoke softly and without conviction. He appeared to merely give a reply to a question.

He had plenty of company, too, even though most of the Red Sox avoided the clubhouse traffic with a postgame snack in the off-limits trainer's room.

With his team down 0-3 in the best-of-7 series and on the verge of being swept by the A's for the second time in three years, even manager Joe Morgan measured his words.

Asked what message he had for the team to keep up their attitude, Morgan said: "Very simple. Tell them to go out and win four straight."

The Red Sox have about as much chance of doing that as they have of winning 162 games in 1991.

The Red Sox bounced back from adversity often in winning the AL East title in a stretch duel with Toronto, the preseason and midseason favorite. Now the bounce is gone.

If they start dreaming, they can check the facts:

- In 21 previous AL playoffs, the opening-game winners have won the pennant 14 times.

- AL teams that have taken a 2-0 lead have gone on to win the pennant 14 times and the World Series 12 times.

- In postseason history, 17 teams have taken 3-0 leads in best-of-7 series, once in AL playoffs and 16 times in World Series play. All of the teams have won the series.

Oakland's Dave Stewart, who beat the Red Sox in the playoff opener last Saturday, said on the eve of his second start, "I don't think they can win four games in a row." Jose Canseco and Rickey Henderson wrote off Boston after two games.

The best of the West is just too good for best of the East. During the regular season, Oakland went 8-4 against the Red Sox, including a three-game sweep in Boston in early September.

"They're an awfully good ballclub," said left-handed Boston reliever Rob Murphy. "They are so well prepared in everything they do. You can't make a single mistake. If you do, they make you pay."

Winless in nine consecutive postseason games since coming within one strike of beating the New York Mets in the 1986 World Series, the Red Sox turned to ace Roger Clemens to try to keep them alive today in Game 4. Although sidelined for 24 days in September by tendinitis in his shoulder, Clemens asked that he be moved up in the rotatioe had won today, he would have benefited from another day of rest."

Morgan said the decision that Clemens try to keep Boston's faint hopes alive was made jointly with the pitcher. However, the manager said, "You have to go by what the man tells you. It's his arm and it's his career."

Morgan had Clemens to pitch on Thursday with hope that the three-time 20-game winner could help out if needed in a seventh game.

Now no one is thinking about a seventh game, scheduled for Boston next Sunday, if necessary.

After winning six of their last eight games, the Red Sox' offense has died. They have 19 hits, but only three runs in three games with Oakland.

"Runs are very tough to come by right now," said Mike Boddicker, the loser in Game 3 although he allowed just six singles with two of the four Oakland runs unearned.