Clever Trevor, a Grade 1-winning millionaire who won the inaugural Remington Park Derby in 1989, was euthanized Friday night due to deteriorating health, according to his former trainer, Donnie K. Von Hemel. The gelding was 30. Clever Trevor had spent most of his life on the Von Hemels’ farm in Piedmont, Okla., where he was cared for by Von Hemel’s wife, Robin, and teenage daughter, Tess. The horse was owned by the family of Don McNeil, who died last year at age 63. Robin Von Hemel said Clever Trevor had been having great difficulty standing in recent days. “In the last few months, he’d become pretty frail,” she said. “The farm feels very different today.” Clever Trevor raced as a juvenile in 1988 through his 5-year-old season in 1992, winning 15 of 30 starts and earning $1.39 million. His best season came in 1989, when he won four of 10 starts and earned $910,470. During his 3-year-old season, he won the Grade 1 Arlington Classic, the Grade 2 St. Paul Derby at Canterbury Park, and the Remington Park Derby. He also finished second to the champion Easy Goer in the Grade 1 Travers Stakes and second to Dansil in the Grade 2 Arkansas Derby that year. “He was a brilliant,” Donnie K. Von Hemel said. “He was a great racehorse who really put a young trainer on a successful path. I was very fortunate that he came along during the early part of my career, and I’ll forever be indebted to that horse. He meant so much to me and my family. It’s a sad day, but he had a wonderful life.” Clever Trevor was an Oklahoma-bred son of Slewacide and the Twice Bold mare Little Mary Beans. In his final start in September 1992, he finished second to Irish Swap in the Grade 2 Washington Park Handicap at Arlington.   Remington Park runs the $100,000 Clever Trevor Stakes, for 2-year-olds at seven furlongs, each November. – additional reporting by Mary Rampellini