In 1977, when Edwin Moses won the first of 122 straight races in the 400-meter hurdles, he was a baby-faced 21-year-old with an Afro hairdo. The Edwin Moses who lost for the first time since then last Thursday in Madrid is balding.

Moses' decade-old winning streak was so phenomenal it can only be measured by the changes in the man himself. Moses is the only standard for Moses, the personification of the word "Olympian," standing on a perch above all to be measured by his own standard.

In 10 years, Moses faced hundreds of different competitors, but nobody beat him; some even quit the event out of frustration. Fashions changed, politics went conservative, the U.S. boycotted the Olympics in 1980 and participated in 1984. But none of it affected Edwin Moses, who just kept running away from the competition.

He holds the world record in the 400 hurdles (47.02) and has 14 of the 16 best times in the event. He also has 17 of the best 20 times and 23 of the fastest 30.

There are few comparisons with Moses' level of excellence in any other area of life, let alone sports. Lawyers lose cases, a mother has a bad day with her child, artists fall victim to the excesses of their egos. But, on the track, nothing tripped up Moses.

His mind and body remained seemingly ageless. Mortality appeared to be his only limit. A human body can only go so fast. That seemed the only limit on a man who for amusement used to run down a basketball court, jump up and kick the 10-foot high rim with his foot. That's right, touch the rim with his foot.

Young hurdlers around the world have hunted Moses -- waiting for him to lose a step. They have mimicked his training routines and they have tried to catch him in early season races before he is in top condition.

For 10 years, it didn't matter. They could follow his regimen by having daily massages, training on grass only, charting heartbeats from workout to workout to monitor recovery time and judge physical condition. They could and did wait for word of where his next race would be and suddenly enter. It didn't matter.

But now time and Danny Harris have beaten Moses. Harris, a third-grader when Moses last lost in August 1977, had made defeating Moses his Holy Grail.

Harris, 21, tracked Moses to Madrid last Thursday. Harris had been scheduled to run in Italy on Tuesday. But when he learned of Moses' commitment to a Spanish promoter to run in Madrid, Harris bought his own ticket to Spain.

The race was only Moses' third of the year. Harris, who quit collegiate running to concentrate on challenging Moses, knew that in his previous three races, Moses had won in such middling times as 48.89 (in Columbus, Ohio on May 4) and 49.19 (in Princeton, N.J., on May 17). The word was out in the close-knit, jealous society of world-class hurdlers. He was vulnerable.

Who would get to him first? Or was it just an aberration? Could it be that he had run in races where he had no competition? But that didn't make sense. Moses has always run against his only true competition, himself. Could it be that Edwin Moses was slipping?

Harris, who finished second to Moses in the 1984 Olympics, began to monitor meets worldwide, as well as one man. He had long plotted with his coach, Steve Lynn, to find a strategy to beat Moses. "We felt if we came off the 10th hurdle together {with Moses}, he could be beaten," said Lynn. "But no one has ever been there with Moses before."

As the Madrid race began, Moses took his customary lead. But Harris caught up and ran even with him over nine hurdles. Moses' foot hit the 10th, knocking him off stride. Harris, who could be seen on videotape watching Moses out of the corner of his eye, seemed to get an injection of energy as he saw his rival hit the hurdle. He saw his chance to win. And he grabbed it. Harris hit the tape .13 seconds ahead of Moses.

It took the best race of Harris' career -- 47.56 -- to beat Moses, a man 10 years older.

"I ran a good race," Moses said afterward. "It's very early in the season for me to be running in Europe. I'm not as sharp as I would be normally. This is one of my best times for so early in the season. I'm not at all disappointed with the race I ran."

Even though the streak is history, Moses continues to compete with himself, by himself. Outwardly, he was indifferent to the Madrid result. But Edwin Moses is not indifferent to defeat. He is aiming at his own world record, beating the best of Edwin Moses at the TAC national championships in San Jose, Calif., in late June.

"I'm pretty sure I'm looking for a world record," Moses told reporters, limiting his conversation to himself. And what about Danny Harris? "If I run as well as I can," said Moses, "I don't think he'll be able to beat me in the future."

In April 1985, Moses was asked if he feared any competitor. "Once I'm in shape," he said, "there's nothing they can do. Nobody can walk on a track and beat me unless they have an extraordinary day and I have a bad day, which I keep from happening."

Now that it has happened, it is all the more evident how spectacular Edwin Moses has been over the past 10 years. We have witnessed an Olympian of the ages in his prime.