Sprint legend Usain Bolt underlined his greatness by retaining his Olympic 200m title with a dominant performance in the final in Rio. The Jamaican claimed the eighth Olympic gold medal of his career in a time of 19.78 seconds.

Bolt, 29, did not show his best form but still coasted away from a world-class field around the bend and maintained his lead in the finishing straight. The silver medal went to Canada's Andre De Grasse, who finished in a time of 20.02 seconds, while the bronze medal went to Christope Lemaitre of France, who recorded the same time as Great Britain's Adam Gemili of 20.12 seconds.

Bolt said afterwards he was relieved to have won the race. "It is something you work so hard for and when the moment comes you are happy and also relieved. The fact I came here and everything worked out it is a brilliant feeling," he told the BBC.

"I am getting older, I am not as young and fresh but I am excited I got the gold and that is the key thing. I focus on what I need to do because if I don't there will not be a Usain Bolt."

Usain Bolt
Usain Bolt retained his 200m Olympic title in Rio Getty Images

He admitted, too, it was likely to be the final time he raced over the distance. "I said when I come to the [World Championships] in London next year it would be 100m and that's it," Bolt explained. "My coach has a way of trying to convince me, but personally I believe this is my last one."

By contrast, Gemili admitted he was devastated by his fourth-place finish. "I am heartbroken. I put so much into that run. I lost my form at the end and to get so close at the end is heartbreaking," he shared.

"I am absolutely gutted. I was in the inside, I knew Bolt would go and a lot of others would try and go with him.

"Myself and my coach had said beforehand to let them go and save some energy. I did but I lost some form at the end but it has been a fantastic season. I have had such fantastic support but I am gutted I could not bring home a medal for Team GB."

Away from the athletics, Great Britain's Jade Jones defended her Olympic title in the -57kg taekwondo category with victory against Eva Calvo Gomez of Spain. The 23-year-old produced a stunning performance in the third round to defeat her much-hyped opponent.

The Bodelwyddan-born athlete led throughout the gold-medal contest, but showed remarkable maturity under pressure to claim the second gold medal of her career. Indeed, Jones produced a series of stunning combinations with the score at 6-7 at the end of the second to power herself to glory.

Jade Jones
Jade Jones retained her Olympic title in Rio. Getty Images

"It feels unbelievable. I didn't realise how much pressure I would feel but to pull this off is amazing," Jones subsequently told the BBC. "I am still young so to be double Olympic champion already is crazy. I've been crying in between sessions because I was so stressed but I did it when it mattered. I'm buzzing."

Meanwhile, on another successful night for Team USA, Ashton Eaton retained the decathlon title he won in London four years ago, while Ryan Crouser won gold in the men's shot put with an Olympic record throw of 22.52 metres. With his victory in Rio, Eaton has become the first man since Great Britain's Daley Thompson in 1984 to retain the decathlon title.

Ryan Crouser
Ryan Crouser is the new Olympic champion Getty Images

Their successes were supplemented by the widely anticipated triumph of Dalilah Muhammad, who stormed to a superb gold in the women's 400m hurdles final. The pre-race favourite finished ahead of Sara Petersen of Denmark, who took silver, and teammate Ashley Spencer, who claimed bronze.

On the golf course, Great Britain's Charley Hull is tied third, two shots off the lead, after two rounds in Brazil. The 20-year-old shot a five-under round of 66 to move to eight under, meaning she is now two shots adrift of South Korean leader Inbee Park.