Roger Staubach retired from the Dallas Cowboys at age 38 today, but both the quarterback and Coach Tom Landry left the huddle ajar for No. 12's return should the team run into injury problems replacing him.

If the heir apparent to the quarterback job, Danny White, were to go down with an injury in training camp this summer, Staubach said, "That would be a real problem for the Cowboys. I'm not adverse to helping . . . I would have to cross the bridge if it develops."

Landry, who encouraged Staubach to keep playing because in the 1979 season "he played better than he did five years ago," said, "if the team needed him, he'd play."

What was rumored from the moment a scrambling Staubach threw his very last pass -- completed illegally to guard Herb Scott in a playoff loss -- came to an emotional reality today at a Texas Stadium press conference. Itwas televised live by three TV stations with three radio broadcasters doing live play-by-play of proceedings that attracted 200 newspapermen.

"The system was successful before me, it's been successful with me in the '70s and it will be successful without me," said Staubach, who earlier had announced his retirement to his old teammates, stopping by the training camp to thank "all my great receivers," Drew Pearson, Tony Hill, Herb Scott."

Staubach said he had to joke there to keep from breaking down. Tears came to his eyes at Texas Stadium, and his chin quivered again the moment when he said, "of course, the nuts and bolts of the Dallas Cowboys. . . ."

His voice broke.

He nodded toward Landry, sitting at a table 75 feet away.

". . . is the man who wears the funny hats on the sidelines."

Staubach gathered himself up.

"I wasn't going to do that," he said, "but Tom Landry is the nuts and bolts, and I appreciate him. . . . I thank the Cowboys and I'm retired."

Though Staubach suffered five concussions last season and six in a calendar year, he downplayed subsequent neurological examinations when he told the press conference today the barest of details, saying only that a New York doctor "expressed more concern" than his Dallas examiner.

"Nothing said I should not play," Staubach said, adding, "if that's the only reason, I wouldn't retire because of it. Injuries are part of football."

The quarterback who won two Super Bowls said the concussions were part of a complex equation of family, health and athletic factors that added up to "a gut feeling" it was time to quit.

Part of that equation may have been his wife's fear of his next concussion.

"I've always been really calm at games," Marianne Staubach told The Washington Post. "But I'm afraid if he had decided to play another season and he went down with a head injury, I probably would just come unglued right in my seat for fear of the worst."

Marianne Staubach is a former registered nurse. The Staubachs have five children, four daughters and a son, whose ages range from two to 13. She said she was the first to recommend that her husband see a neurologist.

That was early in the season. Tests showed no damage. Marianne Staubach said the postseason tests in Dallas revealed no damage, either, but she said the New York doctor "recommended Roger not play."

Now that Staubach has made his retirement announcement, Marianne Staubach said, "I'm relieved."

Another part of the equation, Staubach told the press conference, was his desire "to spend more quality time" with his wife and children, perhaps even shepherding his three oldest daughters to their soccer games.

Athletically, Staubach still has it. The NFL's all-time leading passer statistically, Staubach led the league last season for a fourth time.

The very idea of retiring got in the way of continued excellence, Staubach said. He began to think of retiring even during the season, during a season in which the Cowboys started poorly but finished with a prototypical Staubach victory, fashioned when he produced two touchdowns in the last two minutes to beat the Redskins for the East Division championship.

"I knew I would retire when the season was over," he said, "but I wanted to keep the door open. . . . Coach Landry brought out the idea I wasn't going backwards. He let me know I should play another year, could play another year. I told him I didn't know."

"The possibility of retiring went all the way back to last year. As the season progressed, I thought I'd have to give it more thought. Once we started working out (which the Cowboys did today in their offseason program) I thought I'd say, 'Hey.'

"It has not developed. There has been a lingering feeling. It didn't go away this time."

Staubach, whose Cowboys won 96 and lost 35 with him starting, said the Cowboys are in good hands with Danny White at quarterback.

"Both Tex Schramm (the team president) and Coach Landry expressed that they have confidence in Danny," Staubach said. "I wouldn't retire if they were going to flounder. They're not. They have someone who can do the job."

"But can he," said an anxious Dallas reporter, "throw the Hail Mary."

The "Hail Mary" is the label hung on Staubach's late game passes that created victories when defeat seemed inevitable. Staubach brought the Cowboys from behind to win in the last two minutes 14 times; 23 times he did it in the fourth quarter.