Richard, Bertram, and Elaine Klein's Stay Sound, a popular Kentucky-based stakes horse who won the grade III Hawthorne Derby in 1998, has been retired and eventually will have a new home as a stallion.The 6-year-old by Red Ransom -- Whimsical Wolf, by Wolf Power bowed a tendon and, though surgery was successful, the owners decided to retire him. "If he was a younger horse, we may have continued to race him, but we wanted to bring him back (on top of his game), Richard Klein said.Stay Sound last competed Sept. 4, 2000, when he won the Tri-State Handicap on the grass at Ellis Park. In 1998, he won an Ellis Park allowance event in course-record time of 1:38.80 for 1 1/16 miles on the turf.For his career, Stay Sound won seven of 28 starts -- he won six of 21 turf starts -- and earned $438,603. His trainer was Bernie Flint, regular conditioner for the Kleins, who are based in Louisville, Ky.Richard Klein said plans are in the works for the horse's stallion career. "We've got feelers out locally and internationally," he said.