Col. F. Don Miller, executive director of the United States Olympic Committee, said yesterday he is convinced some U.S. and foreign athletes deliberately performed poorly in their events at the Pan American Games last month rather than face tests that could have detected the presence in their bodies of illegal performance-enhancing drugs.

"You never can prove anything, but I saw it happen. I knew the caliber of certain athletes. I know very well what happened in my own heart," Miller told The Washington Post last night. "It's something that happens, and you know it happens and that's it."

Miller declined to say how many U.S. athletes he believes may have deliberately lost in their events to avoid drug detection other than to say "it was more than one."

Asked if he would name the athletes, he said, "No way." He said athletes from other countries had also deliberately done poorly to avoid detection for using illegal drugs.

In another Olympic-related story, the president of the Los Angeles Olympic Organizing Committee rejected calls for exclusion of the Soviet Union from the 1984 Games, asserting that such an action "is clearly not an option of the host country."

The International Olympic Committee has more than 100 drugs on its banned-substances list, and the use of such drugs has become a major controversy in international sports in recent years. That controversy was particularly acute at the Pan American Games, where 16 athletes were found to have illegal substances in their system and were stripped of medals and records set in those Games.

Additionally, 12 U.S. athletes withdrew from competition and left for home rather than face testing for the drugs.

"What hurt me more than anything else, even the use of drugs, was to see them throw their contests so they would not be tested," Miller said. He said no disciplinary action is contemplated against the athletes involved and that they would be permitted to continue to represent the United States in international meets provided they stop using illegal substances.

Dr. Roy Bergman, chief physician for the U.S. team at the Pan American Games, said the instances of athletes' deliberately losing to avoid drug detection "is like the Black Sox scandal all over again," referring to the baseball scandal in the 1919 World Series in which eight Chicago players were implicated in throwing games to Cincinnati.

"I think it's more negative than taking the drugs. Taking the drugs is at least with the intent to win. It's just an anathema to the American way of life for anyone to lose intentionally."

Bergman said testing procedures at the Pan American Games varied from sport to sport and that it was possible for some athletes to win medals in some areas while deliberately losing in others to avoid testing.

In testimony yesterday before the House Committee on Energy and Commerce's Subcommittee on Commerce, Transportation and Tourism, Miller said the U.S. Olympic Committee is acting immediately to eliminate use of illegal drugs by U.S. athletes.

Beginning within the next month, Miller told the subcommittee, U.S. Olympic athletes will be tested for the use of performance-enhancing drugs that are banned by the IOC. Athletes who test positively for the use of such drugs before the Olympic trials are over will be treated on a confidential, doctor-patient basis, Miller said.

But once the Olympic trials are complete, any athlete who tests positively for any of the banned drugs "will not be permitted to represent their country," Miller said.

He said testing could begin almost immediately for some Olympic teams, such as the hockey squad, which will be competing in Sarajevo, Yugoslavia, in just over four months.

Miller said the new program represents the first time all U.S. Olympic athletes will have been tested for use of the banned drugs.

In resisting calls to ban the Soviets from the 1984 Olympics, LAOOC President Peter V. Ueberroth, in a statement to media representatives after meetings with congressional leaders and White House aide Michael K. Deaver, said the Games were awarded to Los Angeles on the condition "that all eligible nations would be welcome in our country."

Ueberroth's announcement followed petition drives on the West Coast and resolutions in the California legislature calling for the exclusion of the Soviets from the 1984 Games in retaliation for the Sept. 1 downing by the Soviets of a Korean Air Lines jetliner with 269 people aboard.

Ueberroth, in town to testify on Olympic preparations before a congressional subcommittee, also discounted speculation that the Soviets would boycott the Olympics because of the controversy over the plane.

The Soviets, he said, spend years preparing their athletes for competition at the Olympics, which is the quadrennial pinnacle of their national sports program, and it's unlikely they would forgo an opportunity to participate.

Besides, said Ueberroth, "they have the best team."