In an office in Washington this morning, a businessman will push all the marketing studies off the side of his desk, pick up the phone and launch a branch office anyhow. An overweight salesclerk will go on the Enzyme Diet; a car dealer and his customer, buoyed by an ineffable sense of the rightness of the moment, will see eye to eye; and a train will come into Union Station on time to the second, because the engineer believed in Joe Theismann when others did not, and now the engineer believes in himself.

That is the power of the roll. It can go on for a long time, for days, for years, for generations. That is why Pete Rose and John Riggins and the Rockefellers and all the watchmakers in Switzerland are good at what they do year after year. There are a million cliche's for it--they are winners, they believe in themselves--but it is a verifiable phenomenon.

There used to be a lot of jokes about Pittsburgh, but then Pittsburgh cleaned up its rivers and polished up its buildings and won the Super Bowl four times in six years, and now nobody makes jokes about Pittsburgh anymore. The television program "60 Minutes" has been on a roll. Mitsubishi Industries has been on a roll, Elizabeth Dole has been on a roll. At the Sports Arena in Los Angeles Saturday night, Roberto Duran was on a roll. The fire in his eyes that had gone out after Sugar Ray Leonard was back, and by the fourth round, as he hammered Pipino Cueves mercilessly, you could see that Roberto Duran had remembered who he was and what a roll was.

Washington now knows, too. It may take a long time before it forgets again.

The roll began late in the third quarter, just as dusk turned the fountains behind the Rose Bowl to velvet and the lights turned the green playing field electric.

A roll is a funny thing. It doesn't need wheels, and yet it can move a team, a 102,000-seat stadium and certainly an entire city like Washington.

The Redskins had been down 17-10 at halftime, and the roll seemed to have stopped in the third quarter. However, something changed; something inevitable began to be realized. It didn't seem to matter suddenly that the Dolphins' Don McNeal had fastened himself to the back of John Riggins, his hands locked for a sure tackle. Because Riggins was on a roll and McNeal was not, after about eight yards McNeal fell away like a discarded, disconsolate thing of no regard. By the time it was dark at the Super Bowl, Riggins had broken the rushing record and then, as if time speeded up on a roll of its own, the Redskins had won; the game was over but the roll was on.

The roll went into the locker room, along with 25 television cameras, and in the 120-degree madness, Rich Milot saw it stop in front of him. He just stood there looking at the roll that he himself had been on, sweat pouring off his forehead, alone in the crowd, suspended in a dream. It was like that around many of the players: very loud but also very quiet.

"We got on the roll in the third quarter," said Dexter Manley. "That's when the tide turned." Outside the grandstands were almost empty, but a few Washingtonians lingered in the California night, as if to marvel at what had happened to them. "It started Friday night when we left Dulles," said Benson Rose. "I could tell by the way people looked at our hog hats that there was no way the Dolphins were going to win."

"It was the first time that I have ever cried," volunteered his friend, Ali Zinatsakhsh of Iran, whom Benson Rose had introduced to American football only a year ago.

The roll had taken Jeris White, in his Super Bowl world champion T-shirt, out of the steamy television-filled madhouse and into the cool air that poured down Ramp 26 into the subterranean lockers.

"Hey," he said, "I'm not into that stuff," nodding towards the mayhem below. "This is my moment and I want to enjoy it."

The Dolphins were off the roll. They had kept up with it for half of a football game, and then it had gone on without them. The roll is like that. You have to keep up with it.

"It wasn't a case of too much Riggins, but he is an awfully good runner," said the talented Dolphin linebacker A.J. Duhe.

The roll also had the power to increase the numbers of Redskins so that yesterday there were not 40 Redskins on a roll, but 4 million--and by the extension of television and because they clearly seemed the popular underdogs, perhaps 40 million. To root is to take sides, a gesture of self-definition that is daring because it says: "I am like them."

Had the Redskins fallen off the roll yesterday, their fans would have, too, by proxy. They would suffer a 24-hour emotional virus in which the world was likely to be a gray and hollow place. Husbands and wives would snap at each other over breakfast this morning and the mood in the office would be bleak. Taking sides is a risky business, and we do it less often than we suppose. Most of life is a siege between impregnable castles of opinion, with both sides evenly matched and victory only a shadow over no-man's land.

But the Super Bowl had a score, and the score was clear-cut: Redskins 27, Dolphins 17.