Professional football players are physically impaired by the time they reach their early 30s. Basketball, baseball, and tennis players might last a bit longer, but usually it isn&rsquo;t pretty, while pro golfers can be competitive, if not consistent, at the highest levels into their 40s.Then there are jockeys. No professional sport is populated with more viable players who have passed half a century. The most famous among them make news with regularity, with stories invariably highlighting their age. And why not? Mike Smith, 52, rode champions West Coast and Unique Bella in 2017 and figures to make more noise with both this year. Gary Stevens, 55, has found a breath of fresh air at Oaklawn Park and is angling for a viable Kentucky Derby ride. Tammy Piermarini, who turned 50 last year, is determined to add to her total as the third&#45;leading female rider of all time. And the last time anyone checked, Perry Ouzts was 64, with 6,888 wins, and planned to be at work in July when he turns 65.Calvin Borel, Jose Ferrer, Stewart Elliott, Martin Pedroza &ndash; the list is long, and the riders who populate the list provide a continuity to the game that is comforting to their fans. But the risks of competing into the twilight of a demanding physical endeavor are ever present. The dangers of the game have no respect for the age of the players, who live by the hoary cliché that requires daily navigation:&ldquo;It&rsquo;s not a matter of if, but when.&rdquo;&ldquo;When&rdquo; came tragically to Jose Luis Flores, age 57, last Monday at Parx Racing, where he went down on the turn when his mount, Love Rules, suffered a catastrophic injury. The 6&#45;year&#45;old son of Not For Love was making his 34th start and coming off a win at a similar class level. Flores had ridden Love Rules in six of his last seven races.Born Aug. 4, 1960, Flores was pretty much the best rider no one ever heard of outside the state of Pennsylvania. He won 4,650 races &ndash; one of only 42 North American jockeys to attain such heights &ndash; and was the leading all&#45;time money&#45;winning jockey in Parx history. After suffering severe head and spinal trauma, Flores was kept on life support long enough for family and friends to gather at his side. &ldquo;It&rsquo;s been a bad week for riders, and that was terrible,&rdquo; said Scott Stevens, Gary&rsquo;s older brother. &ldquo;I knew Jose and rode with him at Canterbury when he&rsquo;d come in to ride the Claiming Crown.&rdquo;Stevens was referring not only to the Flores tragedy, but also to the pile&#45;up at Fair Grounds March 16 in which Miguel Mena fractured his heel and ankle and Kerwin Clark, 58, broke his jaw, at least one rib, and suffered a collapsed lung. On Sunday at Santa Anita, Rafael Bejarano sustained a fractured wrist when his mount broke down in the final race of the day.Scott Stevens, 57, is still dispensing inspiration and wisdom to the young riders of Turf Paradise. Through Tuesday, he was sitting third in the standings to Glenn Corbett, who is 52. In a career of more than 32,000 mounts, 4,766 winners, and a litany of serious injuries, Stevens has had plenty of chances to walk away from the game on two legs. What happened to Flores serves only to briefly rattle a well&#45;tuned knack to deny the inevitability of that day. &ldquo;It goes through your head then right out of your head, because you can&rsquo;t think about it,&rdquo; Stevens said. &ldquo;We take a risk, but we know what we&rsquo;re doing, I guess. Paul Nolan, a good friend, was paralyzed last year and he&rsquo;s still in a rehab center in Minnesota.&rdquo;There are only so many things a rider can do to save his or her own skin out there and still go pedal to the metal. Whether or not skills and reaction time erode with age is a purely an individual issue &ndash; there are young riders who still don&rsquo;t know where they are out there &ndash; and to watch a veteran rider of any age manage a race with surgical precision remains one of the joys of the sport.Still, the clock ticks, and the danger never ends. &ldquo;I know sound horses can break down,&rdquo; Stevens said. &ldquo;But I do try to be careful with what I ride and who I ride for. My agent, Chad Anderson, does a good job with that. It helps that he was once a rider, so he knows what to look for.&rdquo;There have been 156 jockeys killed in North America since the Jockeys&rsquo; Guild starting keeping track in 1940. The only sport with a comparable mortality rate has been Formula 1 racing, which has instituted safety measures that have reduced driver deaths considerably over the past 20 years. Horse racing has taken some of the game&rsquo;s leading practitioners, including Hall of Famers George Woolf, Jack Westrope, and Avelino Gomez, and put Hall of Famer Ron Turcotte in a wheechair for life.Parx Racing canceled the program on the day after Flores went down. Plans will be made for a fitting tribute. In the meantime, riders across the land will continue to go to work this week living into the universal theme of the successful athlete as described by writer James Salter &ndash; a life of sacrifice without end.