Last week in San Francisco, when Chicago defensive tackle William Perry carried the ball twice at the end of the game, most everyone assumed it was a way of tweaking Coach Bill Walsh's nose for using offensive guard Guy McIntyre as a blocking back against the Bears in the 1984 NFC title game.

But Monday night, "The Refrigerator," who weighs anywhere from 308 to 350 pounds, depending on who you believe, nearly terminated one poor Green Bay Packers linebacker while blocking for two touchdowns, and ran like a woolly mammoth through a pile for another. Now it is quite obvious Coach Mike Ditka and the Bears are serious about this.

Perry was clearly the highlight of an otherwise forgettable 23-7 Monday night victory for the undefeated Bears, now 7-0.

Buddy Ryan, the Bears' defensive coordinator who said in training camp the team had "wasted" a No. 1 draft choice on Perry, then 350 pounds, even had grudging praise for his team's new blocking back.

"He's much more spectacular as a fullback than he is a defensive tackle," Ryan said today. "He's still got a long way to go on defense. How much does he weigh? He told me last week he was 312 . . . I know he's still too fat."

But there were no complaints from Walter Payton, who scored those two short touchdowns by hiding behind Perry. "Believe me, this guy is unbelievable," said Payton, the NFL's all-time leading rusher. "I hope they don't keep bringing defensive linemen in there; they'll move out all the running backs . . . He's like a big waterbed that moves around."

Asked if coaches plan for Perry to catch passes or take pitchouts in goal-line situations, Payton said with some degree of seriousness, "They better not."

Perry is believed to be the biggest pro football player ever. Unless Pete Johnson was lying about the amount of his girth a few years ago, Perry, who eats his Fruit Loops from a mixing bowl, certainly is the biggest man to carry a football in the NFL.

Ryan, the defensive coordinator, is still not convinced Perry can play defense, however. "I'd say the jury is still out on how good the draft pick was," he said. "You'll tell that in a couple of years. Right now on defense we use him on short yardage and at the goal-line. He's got no stamina. He's not in shape. He doesn't have any endurance. He has to play one, then rest two or three. He just has to get his weight down.

"If he got down another 40 pounds, he'd probably be a great defensive player . . . His condition is like an alcoholic . . . He's got to change his lifestyle and stop eating."

But Perry, on offense, apparently is no freak show. Asked after the game whether Perry will continue to play in goal-line situations, Ditka said, "There's a good possibility, until we see somebody bigger than him in there to fill the hole."

So there is a good chance that Perry, already dubbed here today as "The Big Back Attack," will continue to do what he did Monday.

On the second play of the second quarter, Perry came in for fullback Matt Suhey, a sixth-year veteran who usually blocks for Payton. But Suhey has never thrown a block like Perry's first. Perry was assigned to block Green Bay's right inside linebacker, the unfortunate George Cumby.

Perry didn't just block Cumby. He knocked the 224-pound linebacker at least two yards deep into the end zone, drawing shrieks from more than 65,000. Cumby seemed to get lost somewhere between Perry's bellybutton and waistline, such as there is.

"I tried to hit him at an angle," Cumby explained. "I figured I'd take a side, but it didn't matter because one is as big as another."

Payton had little trouble following the block for the two-yard touchdown that tied the game, 7-7. Perry described his execution this way: "I had one obligation, to bump the linebacker, (and) whoever else got in my way, take them out, too."

Perry was asked if there was a name for the play. "It's 34-something, 34-lead draw or something. I don't know. I'm just out there. The only thing I know is the snap is on one or two. That's it."

The Bears don't work on the play in practice because their linebackers won't stand for it.

Cumby knows why. About four minutes later, after Payton's 10-yard run left the Bears at the one, the fans stood and chanted for Perry, not Payton. This time, Perry took the handoff himself and just bashed into the end zone.

"It's just having fun," said Perry. "I always said I'd do whatever they wanted me to."

The final wrecking act came with a minute left before halftime. The Fridge was again assigned to block Cumby. He did that with little problem, and when the carnage was cleared, two other Packers had been bowled over into the end zone.

Cumby explained again: "I tried to hit him flush, but I guess he weighs a little more than I do." At least 90 pounds, George.

Payton carried the one yard, through the left side, without being touched, which is virtually unheard of in a short-yardage situation.

"It felt like stealing," Payton said. "He just caved in that entire left side. I walked in. Nobody could see me. He's so wide, he goes up in there and nobody expects him to have such speed and aggressiveness."

Payton thanked player personnel director Bill Tobin, whose reason for drafting Perry was, "I'd rather have him playing for me than against me."

Perry came in once in the second half, on a fourth-and-one. Cumby made better contact with Perry, this time below the waist. And Payton tripped before he could score from four yards.

Packers Coach Forrest Gregg said he was not angered by Ditka's use of Perry, as Walsh was. "I had Pete Johnson in Cincinnati for several years and he was about 280," Gregg said. But the Bears might get a better reading of Gregg's feeling in two weeks in the rematch at Green Bay.

At least one of the Packers, defensive end Donnie Humphrey, said he was "kinda embarrassed, you know, for him to come in and do that to us. I was really shocked to see him early in the game. But the name of the game is winning, and if he can do that, more power to him. I never heard of Chicago having goal-line problems, though."

Perry says he doesn't want to play on the offensive line, and he still feels sacking a quarterback is more fun than scoring a touchdown.

"Everything's fine, everything's great," Perry said. "Take it today, let it go tomorrow."