Bolt seals triple-triple as Jamaica wins sprint relay

Meanwhile, Vivian Cheruiyot set an Olympic record to win gold in the women's 5,000 metres, coming from behind to beat favourite Almaz Ayana of Ethiopia.

Bolt ran the anchor leg to add the Rio relay crown to the 100 metres and 200 metres titles he had already won for a third straight Games.   -  getty images

Vivian Cheruiyot of Kenya celebrates winning the Women's 5000m Final and setting a new Olympic record of 14:26.17   -  Getty Images

Allyson Felix (far right) clinched her fifth Olympic gold medal.   -  Getty Images

Usain Bolt secured a sweep of the three men's sprint titles for a third successive Olympics when Jamaica successfully defended its 4x100 metres relay title in 37.27 seconds on Friday.

Bolt ran the anchor leg to add the Rio relay crown to the 100 metres and 200 metres 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.

Japan was second in 37.60 seconds to take a surprise silver while Canada took bronze after the US was disqualified.

Olympic record

Vivian Cheruiyot set an Olympic record to win gold in the women's 5,000 metres, coming from behind to beat favourite Almaz Ayana of Ethiopia.

Cheruiyot went past Ayana with less than two laps to go and could not be caught as she finished in 14 minutes 26.17 seconds. Hellen Obiri of Kenya took silver 3.60 seconds behind.

Ayana, the 10,000 Olympic champion, finished in third in 14:33.59.

US wins women's 4x100 metres relay

The United States won the women's Olympic 4x100 metres relay on Friday as Allyson Felix became the first woman to collect five gold medals in athletics.

The U.S. team of Tianna Bartoletta, Felix, English Gardner and Tori Bowie clocked 41.01 seconds, the second-fastest time ever, to beat Jamaica on 41.36 and Britain on 41.77.

The Americans had nearly missed out on a place in the final, after Felix dropped the baton when handing over to Gardner in their heat on Friday morning.

But they appealed successfully, arguing that Felix had been impeded by a Brazilian runner, and went through at China's expense after being allowed to race by themselves in a solo heat on Friday evening.