Too often athletes squander their capital: not just their money but that special reservoir of good will and affection that people sometimes convey upon sluggers of several professions. Bug spray commercials come to mind.

Then along comes Willie Stargell in white tie and tails, standing before a 109-piece orchestra and speaking the words of Dr. Martin Luther King Jr. on the 54th anniversary of the latter's birth. "I'm just Willie going about my day, doing what I think is the right thing," said Stargell, who has refused to endorse pork products because he feels they are not good for children.

Retired Pittsburgh Pirates slugger Stargell made his debut performance at the premiere of Joseph Schwantner's "New Morning for the World" (" . . . Daybreak of Freedom . . .") Saturday night at the Kennedy Center with the Eastman Philharmonia. It was moving not only because of the words and the music, which are a celebration of the life of King, but because of Stargell's willingness to take a chance on doing the right thing even if it wasn't his thing.

"He's got a lot of chutzpah," said cellist Margaret Parkins.

"He narrated better than any one of us could have played baseball," said concertmaster David Brickman.

"He burned," said horn player Alex Shuhan.

"I surprised myself," said Stargell. "This big lug can not only swing a bat, he can stand up and chime in with beautiful music and say something with a direct meaning. I get caught up in it."

When it was over, his 20-year-old daughter Precious caught him with a hug and he gave a deep sigh of relief. "We were nervous for him because he's not one to show his feelings," she said. "Baseball did that to him. You can't show the opposition how you're feeling."

Stargell, who is known for his work in fighting sickle cell anemia, said, "It's probably the finest thing I've ever done in my life.

"Playing baseball, playing in the World Series, hitting home runs. To be asked to do something to commemorate such a great man. What he has done compared to what I've done. Playing ball, having fun, that's what kids do. They catch, they throw on the playgrounds. And then someone says, 'I'm going to pay you for what you do on the playgrounds and if you do well, we'll pay you more.' You get rewards. And when it's over with, you feel very good about your achievements. And then on top of that, they see a part of me I didn't know myself. They ask me to do something special and clean and warm. I like it. I'm impressed. I'm flattered. I hope Dr. King's wife and family will feel as good about it as I do."

King's family was not present. But it will get a chance to hear the composition, which will be recorded Friday at the end of a four-city tour. After that, Stargell is going to take his 15-year-old son Willie Jr. fishing in Mexico and listen "to my whiskers grow."

After the Pirates won the 1979 World Series, Robert Freeman, director of the Eastman School of Music at the University of Rochester, said he approached Stargell with an idea that was guaranteed to draw attention to the school and the cause. "There's no question about the fact that I was exploiting his celebrity as a baseball player for the future strength of music," Freeman said. "But I'm too much a music lover to do something not in its best interest."

Then he went to Schwantner, who won the Pulitzer Prize in 1979. Schwantner said, "Willie who?"

His son said, "Willie Who? Dad, that's Mr. Pittsburgh."

Schwantner went to Pittsburgh to meet Stargell, to get a sense of his voice. Then he went to the library to research the text and then he wrote the music. "This is my way of paying dues," he said.

In 1963, when King came to Washington and told the world about his dream, Stargell was in his first full season with the Pirates. In 1968, when King's dream ended in Memphis, Stargell was in Richmond, getting ready for the season. "Anyone with a sense of feeling felt empty as I did," he said. "I felt empty and confused."

Stargell never marched, but he was "directly involved" in civil rights. "I had to eat in the back of restaurants. I used different bathrooms, different water fountains. There's no hard feelings. But it was a hell of a learning experience."

He retired after last season at age 42, after being a member of two World Series champions, sharing a most valuable player award and leading the league in home runs and runs batted in. "I'm really on the top of the mountain. I put a flag to let someone know I've been there," he said, perhaps unconsciously echoing King.

There was one rule they all agreed on: Stargell would not attempt to imitate King. On stage, his voice was firm, measured, resonant, his own, as he invoked another passage, a favorite. "No, we are not satisfied," he said. "We will not be satisfied until justice rolls down like the waters and righteousness like a mighty stream."

"How long?" he asked later. "Not long because no lie can live forever."

Afterward, three stagehands, who bought Pirates caps especially for the occasion, waited to congratuate him (Stargell gave them stars for their hats), along with members of the orchestra. "How long, Willie?" asked one woman, as she reached to kiss him on the cheek.

"Not long," he said.