Usain Bolt secured a sweep of the three men's sprint titles for a third successive Olympics when Jamaica successfully defended their 4x100 meters relay title in 37.27 seconds on Friday.
Bolt ran the anchor leg to add the Rio relay crown to the 100 meters and 200 meters titles he had already won for a third straight Games.
His ninth gold medal drew him level with Paavo Nurmi, the Finn who dominated distance running in the early 20th century, and American sprinter and long jumper Carl Lewis as the most successful Olympic track and field athletes.
Ryoto Yamagata ran a blistering opening leg for Japan, who won a stunning silver for their first Olympic medal in the sprint relay in 37.60, improving the Asian record they set in qualifying.
Trayvon Bromell's dip for the line was so aggressive that he stumbled over and the United States thought they were settling for bronze in 37.62.
The situation went from bad to worse, though, when they were disqualified along with Trinidad and Tobago. TV pictures showed Bromell stepping into Bolt's lane in the run to the line.
"I’m hoping we can an appeal of some kind, but we’re seeing that the result is a disqualification, so I’m hoping we can appeal that," said former world record holder Tyson Gay.
Canada were elevated to bronze after their run of 37.64, a national record which gave Andre de Grasse his third medal of the Games after his bronze in the 100m and silver in the 200m.
