TOKYO—The 100 meters at the Olympics is the event that turns sprinters into kings: Jesse Owens, Carl Lewis, Usain Bolt. On one of the most unusual nights the sport has ever seen, fans, experts, and even the racers themselves needed a lineup card. The race that has long defined Olympic royalty went to a Texas-born Italian who hadn’t cracked 10 seconds until this year. He’s a 26-year-old whose best days before this came in the long jump. He’s a man even the runner in the next lane didn’t really know. At the Tokyo Olympics, Marcell Jacobs is The World’s Fastest Man. “I think I need four or five years to realize and understand what’s happening,” Jacobs said. The Italian crossed the line in 9.8 seconds Sunday night to capture the first 100-meter medal ever for the country better known for its soccer prowess. Pietro Mennea won the 200 at the …