Jockey Corey Nakatani, injured in a spill at Del Mar on Aug. 26, returned to the saddle Wednesday at Santa Anita. Nakatani finished seventh in the second race before coming home second aboard 7-1 Overbidagain in the fourth race. Nakatani suffered a broken collarbone when his mount, Candace In Paris, clipped heels with another horse and fell during the Finlandia Cup Handicap. Candace In Paris was euthanized...Andrew Schweigardt, a recent graduate of the University of Arizona Racetrack Industry Program, has been named director of industry relations for the Thoroughbred Owners and Breeders Association. Schweigardt, a certified public accountant in the state of New York, previously worked in management with the New York Racing Association. A Thoroughbred owner, Schweigardt worked last summer at a full-service horse farm in california...Jockey Miguel L. Rivera was taken to Memorial Regional Hospital on Tuesday for treatment of a possible broken shoulder after his mount, Cutaway, fell to the ground while galloping out following the fifth race at Calder Racecourse. Cutaway, who finished fourth in the race, recovered and walked off under his own power, apparently uninjured...Six-time stakes winner Mellow Roll will enter stud in 2001 at the Anstu Farm of owners Anita and Stuart Subotnick near Millbrook, N.Y. Mellow Roll, who was New York-bred champion 2-year-old male of 1997 for Anstu Stables, captured the Empire Classic and Alex M. Robb Handicaps, plus the New York Breeders' Futurity and the Sleepy Hollow, New York Stallion Great White Way, and Aspirant Stakes. His four stakes-placings included a runner-up effort behind millionaire Coronado's Quest in the Riva Ridge Stakes (gr. II). Five-year-old Mellow Roll (Distinctive Pro -- Tim's Lady, by Oh Say) won seven of 24 races and earned $555,772. He will stand for a private fee...Alexander M. Waldrop, president and general manager of Churchill Downs, will now oversee all of Churchill Downs Incorporated Kentucky operations as he assumes additional duties that include management of Ellis Park Race Course, as well as Churchill Downs' interest in Kentucky Off-Track Betting. Jeffery M. Smith, senior vice president of Churchill Downs Indiana operations, will now oversee the transition of Arlington International Racecourse, which merged with Churchill Downs in September...Peter Berube was appointed vice president and assistant general manager of Tampa Bay Downs and Robert Cassanese was appointed to the newly-created position of vice president of facilities at the Florida track.