They are a study in contrasts: Jon Hyman is an intense, soft-spoken senior from Oxon Hill High School; Greg Early is an easy-going, fast-talking sophomore from Eleanor Roosevelt High School.

But the two share a common denominator as two of the premier cross-country runners in Prince George's County this fall.

Hyman, a fourth-year runner and second-year captain, has finished first in two dual meets and fifth in the Hereford Invitational.

"I don't even think Jon's reached his potential yet," said Oxon Hill Coach Whitty Bass. "He's shown good improvement each year and as his body's matured he's just gotten stronger . . . He could be as good as any runner in the state."

In only his first year of running, Early has won the Anne Arundel Invitational, placed seventh at the Hereford Invitational and finished second in a dual meet with Bowie and Oxon Hill.

"This is definitely just a start," said Early's coach, Dan Rincon. "He's still got a lot of learning to do. But with the talent he has and the work he's putting in, he could be a real presence."

If Early's success has been a sudden rise, Hyman's has been a steady climb.

Hyman joined Oxon Hill's cross country team as a freshman in 1982, but it wasn't until his junior season -- when his frame began filling out and his perseverance began paying off -- that he made his mark.

Hyman quickly developed into one of the county's top distance runners, finished third in the state in the half-mile and fifth in the mile in outdoor track and earned the school's most valuable runner award for both his indoor and outdoor accomplishments.

Discipline, dedication and determination, Hyman says, have been his competitive edge.

"Some people just don't have that level of motivation," he said. "That's really the key to winning. You have to be aggressive. You have to want to win. And you have to work at it."

Hyman has applied those same principles in the classroom. Last year, by taking two advance courses, he held a 4.3 grade point average on a 4.0 scale and scored 1350 on the SAT. This year he has been recognized as a merit semifinalist in the National Black Achievement Awards. His demanding class schedule includes such courses as advanced placement biology and English, calculus, Spanish 4 and research practicum.

"What makes this year even harder," said Hyman, "is filling out all the applications for college, writing the essays and then trying to keep up my grades and run at the same time. It's an extremely large amount of pressure."

Sometimes, he said, "I come home and I feel so worn out and I just say, No, I'm not doing anything."

One thing he is doing is narrowing down the list of colleges he'd like to attend. Hyman, who plans to major in biomedical research and engineering, is currently considering Stanford, Harvard, Brown, Princeton, Duke and Morehouse

"Jon's problem," said Bass, laughing, "is not 'How do I go,' but 'Where do I go?' "

Still unsure if he'll run collegiately, Hyman said he will base his decision on his performance the rest of the season. For now he focuses on coming meets, with an eye toward the state competition Nov. 9.

"This is the time when you've got to dig down and give what you've got," he said. "I'm not one to predict things, but I think we can be one of the top teams in the state. And I also think I have a shot to be one of the top runners in the state. All it takes is work."

Whereas Hyman is driven by a clarity of purpose, Early, who played junior varsity basketball as a freshman last year, still thinks of himself more as a point guard than a distance runner.

Just how he came into cross country is still a mystery to him -- as is his rapid progress.

"When cross country tryouts were beginning," Early said, "I remember thinking, 'Why not?' I always liked running. And when I made it, I didn't really know if I could hang with these people. I never thought anything like this so soon, either. Maybe by the time I was a junior or senior.

"It's really nice, though. Kind of like a dream, you know. Everybody wants to know who you are. Everybody wants to talk to you . . . "

Rincon is gearing Early toward eventually becoming a middle-distance runner.

"If I have anything to do with it," said Rincon, who qualified for the Olympic marathon trials in 1976, "he'll get up to running anywhere between 800 and 5,000 meters. I'd like to see him put in more background work, more running, more miles and build up his strength. He's getting there."

Early, who dreams of one day "getting national recognition and a college scholarship," said now he only thinks of the season at hand.

"I'd love to run on a championship team and make all-Met," he said. He paused, then laughed. "Who knows? Maybe this is my year."