Stewards at Pimlico Race Course today ordered four horses in the 11-horse "triple" wagering field of the ninth race scratched after they showed signs of being tranquilized.

Urine tests were conducted on all 11 horses to determine if they had been sedated but the results were not to be known until Thursday.

The four horses scratched had shown particular signs of being listless and the decision was made by the track stewards after recommendations by four veterinarians. The veterinarians agreed the other seven horses could be allowed to compete.

Shortly after noon, Dr. Davie Paice, the state veterinarian, examined Academic Freedom, one of the horses scheduled to compete in the ninth race, the only event featuring triple wagering.

Shortly after, veterinarian Dr. James Stewart noticed that three horses he had been treating, Sir Lister, Matt's War and Pocketino, were unusually listless and reported his findings to J. Fred Colwill, head state steward.

Colwill ordered all trainers involved to his office, talked with track security people and several veterinarians. He then ordered the tests and the scratching of the four horses just hours before the 4.49 post time.

Track officials refunded $6,867 that was wagered on the horses in advance triple sales. Track mutuel officials said that there did not appear to be any irregular betting patterns in the race, in which longshot Edmund Tudor upset the 3-to-5 favorite, Indigo Star. The triple paid $636.

Richard Dutrow, trainer of Academic Freedom, said, "My horse is asleep, figuratively speaking. He is listless and drowsy. Something's not right with him."

Bernie Bond, trainer of Pocketino, blamed the condition of his horse on the sudden hot weather. "There's not a thing wrong with him," Bond claimed.

Gary Fichter, agent in charge of the Thoroughbred Racing and Protective Bureau at Pimlico, said that he had put four men on the case.