You may have seen the horrible stories out of Virginia Beach. A professor of political science at Virginia Wesleyan said he was beaten unconscious by two masked men who then carved the word "NIGER" into his abdomen. They did it, he said, because they didn't like what he is doing about South Africa.

He is protesting. Dr. Richard Lapchick is the boss of a group organizing demonstrations against South Africa's hateful apartheid laws. If Lapchick and his people have their way, about 40,000 protestors will march into Nashville on March 17. That's when South Africa plays the United States in a Davis Cup tennis match.

So masked men mutilated the professor. That's what he told police. Some people didn't believe him. A medical examiner for the state of Virginia looked at the wounds and said the professor had done it himself. He said the word "NIGER" was not slashed into the flesh the way a terrorist would practie penmanship. Rather, the word was drawn in, precisely, each letter square and in a line. The letters were created in separate strokes, he said, a bit at a time, and that is a sign of hesitation. Terrorists don't hesitate, the state's man said, they slash.

By law, blacks do not move with whites in South Africa. Segregation reaches even into libraries, where the list of banned books includes "Black Beauty," a sweet nothing about a horse whose crime is to carry a title suggesting anything black can be beautiful. The United Nations has condemned South Africa and asked its members to impose economic and political sanctions. Only two weeks ago the United States said it will no longer sell goods to the South Africa police and military.

Why, then, play tennis with them? Whatever happened in Virginia Beach, whether it was a terrorist attack or a sick stunt for publicity, the issue is the same. The United States ought not give credence to the South African government by recognizing the country's tennis team. Kicked out of the Olympics 10 years ago, systematically isolated from international competition in several sports, South Africa yet comes to Nashville next week to play the U.S. in Davis Cup competition, the ultimate in world team tennis.

The U.S. says politics has nothing to do with sports. It will play South Africa because South Africa has abided by all the Davis Cup rules. There is nothing in the Davis Cup rules that says tennis players are responsible for their country's subjugation of people whose skin is not white. So the U.S. will play South Africa. Besides, if the U.S. refused to play, the rules say we would be ineligible for Davis Cup competition the next two years.

Big deal.

Really big deal.

Who cares if we play in the Davis Cup the next two years? Absence seems a small price to pay for doing what is right. Tell South Africa to get lost.

It is nice to be idelistic and say sports has nothing to do with politics and we should keep them separate. Once politics becomes a measure of competition, who is to decide the worthies? Might not the U.S. have been persona non grata when it bombed Cambodia? Why compete with Russia, where political dissent is suicidal? Ideally, we should keep polities out of sports.

In real life, it can't done. The best we can do is hope the politics are innocent. Bruce Jenner won the decathlon at Montreal and ran victory laps carrying two small American flags, a political statement that moved a lot of us to joy.

But the massacre of Israelis at Munich was tragic and already there is talk that Moscow is inventing ways to keep Israel out of the 1980 Olympics. When the politics turn ugly, the games aren't worth the cost. That seems to be the message delivered last week by Ray Moore, one of South Africa's best players.

Moore quit the team. He wouldn't say why, other than he didn't want to be part of the political spectacle produced by the Nashville demonstrations. Long an opponent of apartheid, Moore says he's played for South Africa only because it gave him a forum. But now he has quit, and that's big news in South Africa, where sports is a mania beyond our understanding.

It is more than a game there. It is a nation's pride. In efforts to regain legitimacy in international competition, South Africa has changed some laws. Now blacks can play against whites, but now with them, except in international events. These are small steps, but they are steps taken only when the world took its ball and went home, leaving South Africa alone.

What Ray Moore said, by quitting, is that even South Africans now must tell their leaders that enough's enough.