It's sort of soccer with a plastic disc. . .. . .and it's the 'Ultimate'

Ultimate Frisbee? Well, it's sort of soccer with a plastic disk. Except that you score goals like in football. Then again, you can't run with the disk and, anyway, play is continuous. Which makes Ultimate a unique sport.

Training is important to the top ''professionals'' in the game. During a game they will do a lot of running, jumping, and catching. ''We love to dive,'' exults one player.

To the untrained eye, it may look rather unorganized. But there are strategies involved here, and ever-increasing skill in throwing a plastic disk on target, even in fickle winds.

The problem is that very few people know about Ultimate.

A recent exhibition match in Europe was held at half-time of a soccer match, with some 15,000 in attendance. But when the world championships of Ultimate were held later in the same stadium, only about 500 showed up.

''I want more people to see us,'' says Stephen Mooney, captain of the world-champion Rude Boys (''Rudies'') from Boston, whose team's agility is evident elsewhere on this page. Beginning this year, with backing from a major corporate sponsor, his wish may come true.