If ever there were an NFL playoff quarterback who lived a humble life, it would be Steve Fuller.

He is a replacement, a second-stringer who is starting only because of someone else's injury. His name will appear in the final 1984 Chicago Bears' passing statistics in the middle of a list of five other names, including shotgun quarterback extraordinaire Walter Payton. The others all kind of run together, perhaps because none is known for much of anything other than handing off.

But the Chicago offense isn't all that memorable, either, except for Payton. This team lives and dies with defense. The offense just comes along for the ride.

If this were a movie set, not the prelude to Sunday's NFC championship game, Fuller would have strolled in as an extra, hung around a few hours, picked up his check and walked out.

"I understand the reasons for it," Fuller said of his lack of status this afternoon before the next-to-last practice for the Bears-San Francisco 49ers game Sunday at Candlestick Park.

"We're all tired as a group of being the other guys. It's a label other people put on you . . . It just goes along with the territory."

The territory has moved quickly under Fuller's feet in his six seasons in the NFL. He went from a No. 1 draft choice in 1979 for the Kansas City Chiefs to a journeyman who didn't play a down for the Los Angeles Rams in 1983. (He wasn't injured.)

He showed up in Chicago this season for a couple late-round draft choices and then separated his shoulder in preseason. Not long after he came back, he separated it again, and didn't return until the 23-19 victory over the Washington Redskins last Sunday.

In between his entrances and departures, No. 1 quarterback Jim McMahon injured his back, broke his finger and finally went out for good with a lacerated kidney; replacement and whipping boy Bob Avellini finally was released; Rusty Lisch reaffirmed why he is a little-used backup; Payton took a shotgun snap and, horrified, ran immediately out of the pocket, and silver-haired Greg Landry returned from the U.S. Football League to salvage the final regular-season game.

Who knows who would have been next if Fuller had not been ready for the Redskins. When he was asked about the quarterbacks today, wide receiver Willie Gault said, "I could never play quarterback."

That shortens the list by one.

The revolving door behind center seemingly has stopped now, pushing a very useful player behind the line.

Fuller, who will turn 28 Saturday, has thrown 93 passes without an interception this season. His completion percentage -- 67.9 percent during the regular season -- was better than that of any other Bears quarterback. He fits the Bears' conservative, Midwestern, grind-it-out offense as well as any Clemson quarterback could be expected to; he scrambles well, he effectively swings the ball to the backs and he doesn't make mistakes.

"He makes the big plays when it counts," said Gault. "I had confidence in Steve before, and I have just as much confidence in him now."

When most people hear the story of the '84 Bears, how they won the NFC Central Division with a six-headed quarterback, they usually react in disbelief.

So do the Bears.

"For us, it was kind of unsettling," said tight end Emery Moorehead, the Bears' fourth-leading receiver. "Every week, another guy . . . I think it's a credit to our offense that we won 11 games with five different starting quarterbacks." (Payton never started.)

The Bears rushed almost 300 more times than they threw; 675 to 390. They gained 270 more yards on the ground than through the air: 2,965 to 2,695. Payton, who became the NFL's all-time leading rusher Oct. 7, was the team's leading receiver with 45 catches for 368 yards. Gault, a sprinter on the 1980 U.S. Olympic track team, was just third, with 34 catches for 587 yards.

"It's not a receiver's domain here," he told a cluster of reporters at the Bears' practice site at the El Rancho Tropicana Hotel, the old Oakland Raiders' training facility.

"We (Chicago receivers) haven't done as well as we're capable of doing, and I'm not really sure if we ever will, because Walter's here."

They're all role players, Fuller included. He was on an academic scholarship at Clemson, where he threw to Dwight Clark, now the 49ers' star receiver. San Francisco Coach Bill Walsh was scouting Fuller when he tripped over Clark.

Now Walsh gets to see Fuller again.

"We're not a flashy bunch," Fuller said. "We're not lighting up the scoreboard all the time. We have not done the things San Francisco does on offense, but, you know, we don't try to. Our defense carries us."

The defense wins; the offense perseveres. Payton played quarterback at the lowest point of the Bears' season, a 20-14 loss to arch-rival Green Bay in the next-to-last week of the regular season. The Bears had just lost their second game in a row and, with it, home-field advantage for the first playoff game. It was then they signed Landry to win the final game.

Most of the Bears weren't sure what to think. Gault was a bit more positive.

"I knew we would get someone else," he said. "We had to. I knew Walter could not play quarterback the rest of the year."