He raced with success from age two to four, scoring wins in the important 1969 Withers Stakes and Arlington Classic.

His performances earned him United States Horse of the Year honors.

The horse won the San Carlos Handicap less than a week before Guggenheim died.

He won his final race, the Hollywood Gold Cup, in which he carried 134 pounds.

At the end of the year, Ack Ack was retired to stand at stud at his birthplace of Claiborne Farm near Paris, Kentucky, where he sired 40 stakes winners, including champion sire Broad Brush and Youth, the 1976 American Champion Male Turf Horse, which won a combined four Grade/Group 1 races in France, Canada, and the United States.