Spend a Buck was named 1985's horse of the year yesterday.

He was the top choice of all three racing organizations that participated in the voting, and he will be honored at the Eclipse Awards banquet in Miami tonight.

The results of the balloting came as no surprise; Spend a Buck already had been voted the champion 3-year-old. Nevertheless, the selection was tinged with controversy because Spend a Buck scored his major victories with the aid of the drug Lasix, and probably could not have won any titles without the medication.

Spend a Buck was treated with the anti-bleeding medication before he scored his outstanding, 5 1/4-length victory in the Kentucky Derby. He had Lasix, too, when he ran his final race in the Monmouth Handicap, beating older rivals in his only try and probably clinching the horse-of-the-year title. He finished his seven-race season with five victories, one second and one third, and earnings of $3,552,704.

Owner Dennis Diaz announced Spend a Buck's retirement Sept. 14, saying the colt had a problem with his ankle. But he also knew that the major races that lay ahead of Spend a Buck -- the fall championship series and the Breeders' Cup -- were held in New York, where all medication is forbidden.

When Diaz chose to avoid these big races, there wasn't much sentiment to honor Spend a Buck with an Eclipse Award. But, one after another, potential candidates for horse of the year kept knocking themselves out of contention. Chief's Crown could have taken both the 3-year-old championship and the horse-of-the-year title if he had won the Breeders' Cup Classic, but he was soundly beaten.

The Eclipse Award voters -- members of the Daily Racing Form, the National Turf Writers' Association and racing secretaries of the Thoroughbred Racing Association -- were left with no viable alternative to Spend a Buck. The colt received 74 of the 201 votes cast. Proud Truth was a distant second with 40.

To Diaz, however, the results of the voting were an unqualified tribute to the horse and a vindication of his management. "The Derby and the Eclipse itself mean there is no longer any need to explain anything to anybody," he said in Miami yesterday. "I could go on a 15-minute tirade of vindication, but it's been done for me."