Jamaica's Usain Bolt, left, crosses the line ahead of American Justin Gatlin to win gold in the men's 100-meter final Sunday.Usain Bolt, the consummate showman in a sport that badly needs its credibility and entertainment value restored, again showed why one short sprint and one tall sprinter can captivate millions of people around the world.The lanky Jamaican on Sunday became the first man to win the 100-meter dash in three consecutive Olympics, blazing to the finish line at Olympic Stadium in 9.81 seconds. He went past American Justin Gatlin as if Gatlin were standing still, which he certainly wasn&rsquo;t. Gatlin was second in 9.89 seconds, and Andre De Grasse of Canada --&nbsp;who won NCAA titles in the 100 and 200 while competing for USC -- was third in a personal-best 9.91 seconds.Bolt soaked up the crowd&rsquo;s attention before the race, as he always does, animated while others are quiet, outwardly expressive while others are straight-faced and focused. He pointed to the camera, gestured to the adoring crowd and performed his usual routine of putting his index finger over his mouth and then, as he settled into the blocks, crossing himself and pointing his index finger to the sky.He had served notice during his semifinal heat, a few hours earlier, that he was poised to do something special when he was clocked in 9.86 seconds despite easing up about 15 meters from the finish line. He lived up to that promise in the final, running in Lane 6, again next to De Grasse, who seemed to be pulled along in Bolt&rsquo;s magnetic wake.Bolt walked a victory lap around the stadium, holding a stuffed version of the Rio Olympic mascot that someone had handed him before going over to the stands to embrace and be embraced by fans. De Grasse wrapped himself in a Canadian flag and jogged around the track joyously.Bolt will also compete in the 200, the event he won in the last two Olympics, and will go for a triple-triple of winning the 100, the 200 and the 400-meter relay in three straight Games.He didn&rsquo;t have a great start Sunday but hit stride in the middle of the race and easily passed the front-running&nbsp;Gatlin, who was to his left, and everyone else. &nbsp;That he would win a third straight gold in the event seemed unlikely when he injured a hamstring and missed the Jamaican national championships, but he was given a medical bye onto his country's Olympic team and healed quickly.