SHEILA WILEY STILL ISN'T CERTAIN why she picked Dexter Manley as her hero. She only knows -- and so does he -- that she was the very first fan Manley ever had in Washington.

She was 9 then, and he was 21 -- an obscure fifth-round draft choice with long legs, a massive chest and a penchant for rudely introducing himself to opposing quarterbacks, as in, "Excuse me, Mr. Manley, but would you allow me the pleasure of unscrewing my head from this piece of sod?"

It began innocently enough for Sheila, now 12 and a seventh-grader at Hill School in Middleburg, Va. She began watching Manley on television and liked his style. Soon, she was combing the newspaper for pictures of her man and pasting them all over her bedroom wall. She also wrote to him and enclosed pictures of herself.

La year, she became a bit bolder. At Christmas, she mailed biscuits to Manley's dog and a small gift for him, too. When Manley called to thank her personally, her mother jokes that Sheila didn't wash her ear for weeks.

But all was not sunshine and sacks for Dexter Manley last year. Teams were double- and tripled-teaming him, and his play had fallen off. He was even being replaced occasionally by another promising youngster, Charles Mann. In the off-season, there were reports the Redskins were considering trading Dexter Manley. But Sheila Wiley stood by her man.

She fired off a three-page, handwritten letter to a family friend, a fellow named John Cooke, son of the Redskins' owner and himself being groomed to take over the team.

"On the news I heard they were going to trade Dexter," she wrote, then demanded, "Why? He is still good. And if you do trade him, then that means I have to move with him and still root for him . . . And that would mean I would have to throw away all my pictures of him. I have at least 16, and they all say Dexter Manley, Washington Redskins.

"I cut out huge letters that spelled Dexter Manley and hung them on my wall. What will I do with them? If by chance he does get traded, everyone is going to tell me what a loser I picked. And that's not TRUE! . . . He is really trying hard this season, I know, and I hope to see him on the field next year. Please talk to the coaches and tell them to give him a good chance . . . He wants to STAY!! Please let him!"

And there was a P.S.: "I know I'm just a kid and no one is really going to pay much attention to this letter, but Dexter is my whole life of football. I'm not just saying this to make you change your mind."

It is not known whether Cooke consulted with his father or with Joe Gibbs and Bobby Beathard before he wrote back and assured Sheila that Dexter Manley would not be traded.

"Enough already," Cooke wrote. "He stays."

And so it was on a sultry summer day in July that Sheila Wiley made her first pilgrimage to Carlisle, Pa., to worship at the feet of her football hero.

I had promised my children a visit to the Redskins training camp, and Sheila and her mother, Helen, a family friend, were invited along. Sheila had her camera -- and her autograph book, of course -- and only one mission in life that day: She was going to meet Dexter Manley, face to face.

I have always had some difficulty understanding the fascination many people have with athletes. I have seen grown men admired and respected in the business world very nearly groveling at the feet of a Sonny Jurgensen or a John Riggins. I have seen children nearly hyperventilating at the prospect of shaking hands with Pat Fischer.

As a reporter covering a football team, I have a different view. I was able to get up close and personal, to see these huge men not so much as fotball players, but as human beings with most of the problems and insecurities the rest of us have. They were always accessible to me, so there was no great mystery. Theismann? Just a regular Joe, when you get right down to it.

Still, try telling that to a 12-year-old. I didn't even bother. But on this day, Sheila Wiley found out for herself.

Old Redskin writers get a few privileges in training camp. While most of the 300 people on hand that day to watch the team practice could only sit in the bleachers and watch the action 300 yards away, I was allowed to wander out near the field. My children, Jennie and Emily, and Sheila tagged along.

Sheila, of course, headed straight for the defensive linemen. "There he is," she said, pointing toward Manley. "He's wearing a little white hat. Oooh, he's soooo neat."

She didn't take her eyes off Manley once for the next 90 minutes, and when the players began heading toward the locker room, Sheila was not far behind.

Finally, the great moment was at hand. I had asked one of the trainers to see if Manley would mind coming out to meet one of his biggest fans, and soon, her little hand was being shaken in the massive mitt of a man who stands 6 feet 3 and weighs 250 pounds.

"Sheila? Oh yeah, Sheila Wiley," Dexter Manley said, his face breaking into a broad grin as he looked down at the little girl. Of course he remembered her. In fact, he said, he even carried around the pictures she had sent of herself. "Got 'em right here in my backpack," he said, opening it and showing her the wrinkled snapshots.

I left Sheila and Dexter alone for awhile. They talked for more than 20 minutes under a hot summer sun. Dexter signed everything Sheila gave him, posed for pictures with her, with her mother and with my kids, then gave her his address and telephone number, in case she ever needed to get in touch just to talk. He even invited Sheila to his wedding this fall, and she went.

While all this was going on, my own children were scurrying around for autographs, corralling every Redskin in sight. I even found myself, the cool, dispassionate newspaper reporter, pushing them in the right direction, trying to separate the rookie riffraff from the real Hogs and Smurfs.

Every player, without exception, stopped to sign. Some even stood still long enough to get their picture taken. Theismann, in fact, insisted on a group portrait with my children. He made their day. Mine too.

Soon, we were back on the road again, and the miles flew by with excited chatter about Joe T. and Dexter. It was mostly all Dexter.

Sheila Wiley had met her Manley, and he was all she thought he would be and more.

Better still, he stays.