Usain Bolt, the greatest sprinter of modern times, retired from the Athletics world. But the farewell ended in pain as he injured himself while running the last lap of the men’s 4x100m relay race at the World Athletics Championships in London. While running the final race of his career, the 30-year-old Bolt, after taking the baton from his Jamaican teammate Yohan Blake, suffered cramps on his left hamstring as he tried, in vain, to chase down his rivals in the race. Since 2008, when Bolt set his first world record, he had not lost a championship race and collected 19 gold medals in 100, 200 and 4×100 meters. The only time, he did not win the gold was in 100 meters at the 2011 world championships, when he was disqualified for a false start and the 2008 Olympic 4×100, a gold won by Jamaica that was subsequently stripped because a teammate tested positive for banned substances.