LOUISVILLE, Ky. — Hall of Fame horse racing trainer D. Wayne Lukas has been hospitalized and will not return to training, Churchill Downs announced Sunday after speaking with members of his family.

Lukas’ family said the 89-year-old has battled a severe infection that has worsened and that he has declined an aggressive treatment plan to instead return home. His horses have been transferred to assistant trainer Sebastian “Bas” Nicholl.

“Wayne built a legacy that will never be matched,” Nicholl said. “Every decision I make, every horse I saddle, I’ll hear his voice in the back of my mind. This isn’t about filling his shoes — no one can. It’s about honoring everything that he’s built.”

Lukas is one of the most accomplished people in the history of the sport. His 15 Triple Crown victories are second only to good friend Bob Baffert, and Lukas has a record-tying 20 in the Breeders Cup.

He won the Kentucky Derby four times since 1988. His most recent victory in the Triple Crown came last year with Seize the Grey in the Preakness, his seventh — one short of Baffert’s record.

“Wayne is one of the greatest competitors and most important figures in Thoroughbred racing history,” Churchill Downs president Mike Anderson said. “He transcended the sport of horse racing and took the industry to new levels. The lasting impact of his character and wisdom, from his acute horsemanship to his unmatched attention to detail, will be truly missed. The enormity of this news is immense, and our prayers are with his family and friends around the world during this difficult time.”

Lukas is affectionately known around the barns and the racetrack as “Coach” because he coached high school basketball before his professional career with horses began. Even with months to go before his 90th birthday, he would get up on his pony in the early morning hours and go out to the track himself, rather than letting his assistants do the day-to-day work.

Born Darnell Wayne Lukas on Sept. 2, 1935, in Wisconsin as the second of three children, he rose to prominence in the sport with quarter horses in races that are effectively sprints. He moved into thoroughbreds in the late 1970s and won his first Preakness with Codex in 1980.

Lukas has 4,967 documented victories in thoroughbred racing, with his horses earning more than $310 million from over 30,600 starts.