TOKYO — Perhaps it was an ominous sign, or maybe just a normal one, when BMX racing at the Olympics began on Monday with a training run collision between a top cyclist and a marshal who wandered onto the track.
When the competition began on Thursday, a Japanese rider flipped over her handlebars in the first heat, ending her Olympic experience in less than a minute and sending her away with a broken collarbone.
Friday, the day the medals were doled out, began with a thunderous downpour, which felt right, because BMX is high in drama. Water slicked the course, merely adding to the danger factor. Reasonable minds delayed the start and sent workers onto the paved serpentine course of rollers and high-banked turns with brooms and dryers.
Yet it was just off the track where there was something more telling: five teams of medics, each armed with a stretcher, spread around the course. Behind the main scoreboard, three ambulances idled.
The danger inherent in the sport — part of its allure and part of the reason it is here at the Olympics — became most apparent during the semifinals, when Connor Fields of the United States, the gold medalist at the 2016 Rio de Janeiro Games, crashed on the first turn of a semifinal heat. In a split second, two trailing riders tumbled on top of him.
Fields was carried off the track after several motionless minutes. His jersey was shredded by the fall, and his hip and shoulder were bloody with road rash. Racing was delayed about 30 minutes as he was taken to an ambulance and eventually driven away.
“We can confirm that Connor Fields is awake, stable and awaiting further medical evaluation,” the American team’s chief medical officer, Dr. Jon Finnoff, said through a U.S.A. BMX spokeswoman. “Additional updates about his condition will be shared as they become available.”
BMX is part of the growing X Games-ification of the Olympics, perpetually in search of sports that might appeal to younger viewers in ways that, say, modern pentathlon or dressage do not. BMX’s freestyle discipline was added for Tokyo, along with skateboarding, surfing and sport climbing.