It ended with a touch of Steeler class, and the ABC cameras, apparently quite by accident, let us be witnesses. Of the sad and silly scenes that followed an Oakland Raider victory that just might have ended the last NFL dynasty Monday night, the best barely made the top-left corner of our televisions: Joe Greene seeking out Mark Malone.

The oldest important Steeler and the youngest had played grandly, although not well enough. And Greene, who can be as serene after a game as he was mean during it, wouldn't let the new quarterback take more than a few steps toward the clubhouse without telling him so.

From Greene, a gesture can mean more than words. And Malone, once the immediate bitterness of losing began to fade, surely cherished the moment the cornerstone of a team as special as any in NFL history sought him out, squeezed his arm and hand in a way that said he belonged.

Once on a desperate night such as this, Greene and the other Steelers could have carried a kid quarterback after Terry Bradshaw suffered a broken bone in his right hand. Five years ago, their shoulders had been wide enough to do that very thing.

Five games into the 1976 season, the Steelers were 1-4. And when Bradshaw was sidelined with neck and back injuries during a loss to the Browns, an obscure rookie, former Washington-area schoolboy Mike Kruczek, was the replacement.

Challenged, stunned out of obvious complacency after back-to-back Super Bowl victories, the Steelers nearly won that day. They did not lose again until the AFC championship game. In all, they won 10 games in a row, six of which Kruczek started.

From the sixth through the last regular-season game, the Steelers allowed just 28 points. They had five shutouts and two other games in which opponents mustered no more than a field goal. Kruczek threw no touchdown passes; he also was intercepted only three times.

Mostly, he handed the ball to Franco Harris and watched Giants, Bengals, Dolphins and others bounce off a defensive line aptly called the Steel Curtain. Only the rarest of teams can go on such a league-wide pillage with little more than a minimal contribution from its quarterback.

With Bradshaw healthy, but Harris and Rocky Bleier unable to play, the Steelers lost the AFC title to a Raider team that later won the Super Bowl by 18 points.

As Monday's game showed so vividly, many of those peerless Steelers and Raiders either are gone or in serious decline. Five years ago, Gene Upshaw and Art Shell obliterated a strong Minnesota Viking offensive line in the Super Bowl, like tanks moving against motorcycles. They are no more than spot players now.

The Steel Curtain seems like lace. It has slits, large enough for ordinary runners to slip through for nice gains. In its glory years, the front four was Greene, a fat tackle and two greyhounds rushing the passer. Greene and L. C. Greenwood remain, as proud and possessed as Upshaw and Shell. And as vulnerable.

The state of the '80s Steelers can be illustrated by one play Monday night in Oakland. Greene had returned to the lineup and was at his familiar 45-degree angle toward the center just before the snap, seemingly ready to tear off his right ear.

Came the snap. Came Greene's burst. And the usual double team, the center bouncing him toward the right guard. Greene never got close to the quarterback. Scratching and pounding as fiercely as ever at age 35, the first of the great Steeler draftees could not get near enough to Marc Wilson to rattle him with a naughty word. Nor could any of the other Steelers.

After enough time to contemplate a law brief from the Raiders' suit against the NFL, Wilson threw a ball spiraling with more hope than hum. Bob Chandler took it away from Dwayne Woodruff in the end zone. The Raiders bumbled more than enough for Pittsburgh to win. But the Steelers are not the toughest NFL alloy any more.

They still might make the playoffs. As we have learned from the Redskins, even ordinary teams, ones with weaknesses a first-time customer would notice by halftime, remain in contention with two weeks left in the season. Parity helped weaken the Steelers; it will help fuel their last surge.

The team of the '70s, Pittsburgh missed the first full playoffs of the '80s. It has had an extraordinarily low turnover rate from its first Super Bowl success seven years ago. This is partly because the sentimental side of Coach Chuck Noll cannot easily part with such as Greene and partly because his pragmatic side realizes the younger replacements are not any better.

A man plays the first five years in the NFL for the money. Any more means he's hooked, deeply in love with a way of life few who have not experienced it can appreciate. After the fifth year, he's willing to cope with the pain and the politics. He often plays harder his 12th year than he did his second.

Lately, with all the changes in scheduling and the playing rules, emotions probably are more pivotal than ever. Who wants to win, who has to win more might be the most significant factors now. Because nobody can drift through a team's collective mind, NFL handicapping often is folly.

Knowing this might be their last struggle, the Steelers were terrific the three games prior to Monday. The defense caused sacks and turnovers at an uncommon, mid-'70s rate. In Oakland, they were hit by a team with more than a pound of pride itself.

Probably, the defending Super Bowl champs will not make the playoffs.

Malone threw a scare into them. The Raiders surely were close to cocky when Bradshaw went down and a second-year quarterback with almost no regular-season experience came in.

The Steelers have been more an offensive than a defensive team for a few years, and their receivers helped Malone as much as that is possible. Still, he often threw well, showed himself a fighter trying for the impossible knockout to the end.

Greene is drawn to such players; he has been one himself for some time.