Fenway Park turned into a Roman Coliseum last night. The riotious fans of Beantown got what they have lusted for all season - not just Yankee defeat, but Yankee blood.

The final inning of this 9-2 Boston victory over New York was one long tumult. Visions that Boston fans had nurtured all winter since the sorrows of '77 became sweet reality.

The standing throng, 32,312 strong, begged for home runs to add salt to the Yankee wounds, then got them. The Bosox entered their last at bat with a safe 7-2 lead, but that was not enough.

James Augustus (Catfish) Hunter, the first free agent, the symbol of Yankee dollars, the noble veteran, took the mound for that eighth inning.

Hunter, just off the disabled list, was merely trying to get an inning of work at the end of this laugher.

But no Bostonian would let him forget his last appearance here just one June ago when the Red Sox greeted him with four first-inning home runs to ignite their 16-homer weekend.

When Fred Lynn, first to face Hunter, blasted a 3-2 pitch through a stiff wind into the Boston bullpen, the insanity of Fenway returned, the crowd standing and pleading for more.

George Scott, the next batter, hardly disappointed them. The Boomer argued with plate umpire Bill Haller on every pitch, going nose to nose. Finally, on a 3-2 fast ball, Scott crushed a missile into the night - a towering homer into the center-field screen.

As Scott ambled home, Haller waited for him, ear cocked for any comment. Haller even followed Scott to the Boston dugout, waiting for any excuse to eject him.

The crowd filled the air with "Boomer," "Boo," and laughter. "Just like last year," said Scott, who delivered the last of those 16 homers in three games. "They begged for it and the Boomer gave it to 'em."

When tiny leadoff man Rick Burleson followed three batters later with a long blast to left, the crowd could not believe that these home-runs-on-demand could continue. Not quite. Burleson's blast hit inches from the top of the wall. Finally, with the bases loaded around him, the still-proud Hunter fanned Carl Yastrzemski to get back to the bench unaided.

The fans of Fenway have started what may be a tradition this year, one that has helped boost the Sox to the 30-6 home record that has launched them eight games ahead of New York.

With two out in the ninth, the entire crowd rises - if it thinks the Boston pitcher worthy of such honor - and begins one long cheering, chanting, clapping ovation until he has gotten the final out - no matter how long it takes.

Boston bats were the instruments of Yankee punishment tonight - seven balls including a Butch Hobson homer, were knocked over or against these old park walls. But Red Sox hurler Dennis Eckersley more than deserved his sendoff last night.

The cocky, sidearming right-hander - the pitcher for whom Boston angled all winter, then landed in trade in March - pitched a mean six-hitter, full of knockdown pitches and sawed-off Yankee bats.

In the ninth he rose to the occasion, overpowering Jay Johnstone for a final called strike that sent the crowd pouring into Yawkey Way, where cars horns blared as though a pennant, not just a midseason series, had been won.

"Now that ," beamed Sox Coach Johnny Pesky, who has matched these duels since the 1930s, "was what I call at-mos-pher-ic."

"I feel so sorry for the Yankees," said Pesky, addressing the rowdy clubhouse in general, "Isn't it too bad?"

Boston, denied a world title for 60 years while New York, has been granted 21, was in no mood for generosity. As hunter struggled - every Boston batter swinging from the heels - the fans chanted, "Six of eight," informing Hunter that six of the last eight men he had faced in Fenway had hit home runs.

George Steinbrenner, the Yankee owner, watched from a sky box as fans taunted him and counted the number of times he refilled the glass in front of him.

"Hey, George," they yelled, "don't kill the whole bottle. You might want to hit Billy with it."

The Red Sox were slightly more restained. True, Eckersley said of his final strikeout, "Johnstone took me deep (on a solo homer in the fifth inning), so I punched him out."

But Eckersley added, "I felt kind of sorry looking at Catfish. I couldn't get into the cheering. My gut kind of turned over watching it."

Only Hunter felt worse.

"My arm hurt all the way from the shoulder down to the fingers," said the once-great hunter of hitters. "I thought it would come off on one pitch. Maybe they ought to cut . . . it off. I'd be better that way."

The Red Sox answered the Yankees' 10-4 victory of the night before in a hurry, scoring six runs in the third. Back-to-back doubles off the left and right-field walls by Yastrzemski and Carlton Fisk scored the first three and Hobson's rifle shot through the wind into the Bosox bull-pen in right finished that outburst.