It is fitting that Sunday&rsquo;s $100,000 Native Diver at Del Mar has intergenerational appeal since Native Diver himself spanned an entire era. He raced 81 times over seven seasons, won 34 stakes, and in 1967 became only the seventh Thoroughbred to earn more than a million dollars. He is also buried at Del Mar.The entrants for this running of the Native Diver include a 3&#45;year&#45;old, a 4&#45;year&#45;old, a 5&#45;year&#45;old, three 6&#45;year&#45;olds, and a 7&#45;year&#45;old. Imperative won the Charles Town Classic. Hard Aces took the Gold Cup at Santa Anita. Point Piper set a track record in the Longacres Mile. Midnight Storm has been a standout on grass, especially at Del Mar, where he has completed the Del Mar Derby&#45;Eddie Read&#45;Del Mar Mile triple.They&rsquo;ve all had their ups and downs, par for the course for a professional racehorse. Native Diver, on the other hand, never had a bad year, which is one way for a California&#45;bred to make the Hall of Fame without winning a classic or a national title.At age 3 in 1962, Native Diver started 11 times and won five races, beginning the season with a narrow score in the Debonair Stakes at Hollywood Park and ending the year with a 6 1/4&#45;length show of force in the Malibu Stakes at Santa Anita.At 4, he ran 15 times and won five, all stakes, while turning in very good performances in losses to the likes of Olden Times, Crozier, and Crimson Satan, all horses with national reputations.At 5, Native Diver went to the well 15 times, running in nothing but stakes. He won six, including the Palos Verdes Handicap on Dec. 26 to open the 1964&#45;65 Santa Anita meet.As a 6&#45;year&#45;old, Native Diver reached his zenith, winning 6 of 9 starts that featured a world record seven furlongs in the Los Angeles Handicap and the first of his three straight Hollywood Gold Cup wins.At 7, Native Diver&rsquo;s age began to show a little. He raced 12 times in seven months and won four major stakes, but he lost races he would have won the year before. Still, he was very much the Diver everyone knew in his domination of the Hollywood Gold Cup.At 8, Native Diver entered what appeared to be a second childhood. He won the West&rsquo;s two most important sprints &ndash; the San Carlos and the Los Angeles &ndash; and added a third Gold Cup at the expense of heavily favored Pretense, a formidable nemesis half his age. After setting a track record in the Del Mar Handicap, his 13th start of the year, he ventured north for a fall campaign, but he was stricken with colic shortly after his arrival. His death on Sept. 13, 1967, shook the California racing colony to its soul.Now deep into his 7&#45;year&#45;old campaign, Blue Tone is the senior citizen of Saturday&rsquo;s Native Diver lineup. The gelded son of Birdstone is coming off a third&#45;place finish in the Marathon Stakes on the Breeders&rsquo; Cup Friday undercard for trainer Bob Hess and owners Cathy and Paul Schroeder and partners.Blue Tone also is trying to bank his first graded stakes win, further proof that it&rsquo;s never too late to make a mark. His smart allowance win in October at Santa Anita certainly puts him in the thick of it, although his three prior efforts require some forgiveness.&ldquo;It turned out he was tying up in his training, but he showed no outward signs,&rdquo; Hess said this week. &ldquo;It&rsquo;s weird that an older gelding would start to tie up. We only were able to detect it by taking blood after his race here in August, when he ran like he had logs for legs.&rdquo;It was a strange turn for a solid professional who had won a pair of listed stakes and finished third in the 2015 San Pasqual to Hoppertunity. Hess trained and treated Blue Tone accordingly, and his two races post&#45;diagnosis have been more like it.Blue Tone&rsquo;s record suggests that he likes Del Mar, with three wins from his six tries there and a second&#45;place finish in the 2014 Native Diver. Unfortunately, those races took place when Del Mar&rsquo;s main track was an aging version of a Polytrack synthetic surface. This will be his Del Mar first start on old&#45;fashioned dirt.&ldquo;He might be a little bit better on the synthetic,&rdquo; Hess said. &ldquo;I don&rsquo;t know why that should be, but the numbers do show it.&rdquo;Of more significance is Blue Tone&rsquo;s current form on dirt at Santa Anita, and that he&rsquo;s still going strong at his age.&ldquo;I&rsquo;ve always admired what Richard Mandella has done with older horses like The Tin Man and so many others,&rdquo; Hess said. &ldquo;I&rsquo;ve tried to emulate that.&ldquo;As a young horse, Blue Tone had little hiccups here and there, so he didn&rsquo;t even debut until March of his 4&#45;year&#45;old year,&rdquo; Hess added. &ldquo;He&rsquo;s a really young 7&#45;year&#45;old, if that makes sense.&rdquo;It does. Blue Tone will be making only his 24th start in the Native Diver. By comparison, Native Diver made his 24th start in the 1963 Hollywood Gold Cup at age 4 and led the pack into the stretch before finishing fourth. Should Blue Tone take a page from Native Diver&rsquo;s playbook Sunday, Hess, a fellow Cal&#45;bred, has promised to lay a flower at the old boy&rsquo;s infield grave.