Semenya, who shattered the 34-year-old national record of Zola Budd to win the longer event earlier in the week, powered to the front early in the two-lap final and never looked like being caught.

She recorded a first lap of 58.66sec and the gap only grew from there.

The 27-year-old eventually set a Games record of 1min 56.68sec to improve upon the previous mark of 1:57.35 set by Maria Mutola of Mozambique at Manchester 2002.

"As a South African, I feel proud," she said.

"I believe we are one of the great nations, especially when it comes to sports.

"When you look at our sporting history, we always do great, in terms of cricket and rugby.

"We try to make sure that we inspire the youth.

"Being able to win the double is a memory I'll never forget but I'm doing this for the youth to show them that anything is possible, if you believe."

Kirsty Wade of Wales was the last athlete to pull-off the women's 800 and 1500m double at Edinburgh 1986 - five years before Semenya was born.

Semenya, who continues to attract attention for her hyperandrogenism, a condition giving her naturally higher levels of testosterone, won world 800m titles in Berlin in 2009, Daegu in 2011 and London in 2017 to go with her Olympic victories at London 2012 and Rio 2016

Margaret Wambui of Kenya took the silver medal today in 1:58.07 and there was a personal best in third for Natouya Goule of Jamaica with 1:58.82. 

Cheptegei was equally imperious in withstanding a late burst from Canadian rival Mo Ahmed to win the 5,000m in a Games record of 27:19.62.

Cheptegei took over 25 seconds off the 27:45.49 time set by Kenya's Wilberforc Talel at Manchester 2002 and secured a fourth consecutive Ugandan win in the event.

Ahmed took the silver medal in 27:20.56 and there was bronze for Rodgers Kwemoi of Kenya in 27:28.66.

New Zealand's Jake Robertson was  fourth.

Katarina Johnson-Thompson took just the third English athletics gold medal of the week by winning the women's heptathlon crown.

The world indoor pentathlon champion never seemed comfortable and temporarily lost the lead yesterday with a poor shot put.

But a 6.50 metre long jump this morning opened daylight and then a 40.46m javelin made the 800m an effective lap of honour.

She laboured home in fourth place in 2:21.24, but this was enough for gold overall with 6.255 points.

Nina Schultz of Canada took second with 6,133 pointsand English teenager Niamh Emerson ran a fine 800m time of 2:12.18 to rise to third on 6,043.

Oluwatobiloba Amusan won a 100m hurdles lacking the injured Australian world champion Sally Pearson in 12.68sec.

The Nigerian held off Jamaica's Danielle Williams by a tenth of a second as her team-mate Yonique Thompson took the bronze medal in 12.97.

There were also three exciting field finals this evening, with a Games record set in each. 

Alysha Newman of Canada cleared 4.75m to win the pole vault and beat New Zealand's Olympic bronze medallist Eliza McCartney, who managed 4.70m.

Australia's Nina Kennedy took the bronze medal with 4.60m as England's Holly Bradshaw cleared the same height but did not finish on the podium.

New Zealand's night of near misses continued as Danniel Thomas-Dodd of Jamaica denied Dame Valerie Adams a fourth consecutive shot put crown.

Thomas Dodd cleared a national record 19.36m as Dame Valerie - who gave birth six months ago - took silver with 18.70m.

Brittany Crew of Canada took the bronze medal with 18.32m.

Jamaica translated their sprinting prowess into the throws as Fedrick Dacres clinched the discus gold with a best of 68.20m in a 1-2 in front of fellow countryman Traves Smikle.

He managed 63.98m for second as Apostolos Parellis of Cyprus finished third with 63.61m.

The night began with a sixth successive medals clean sweep for Kenya in the men's 3,000m steeplechase.

Reigning Olympic champion Conseslus Kipruto set-out close to eight minute pace and, although he slowed, he was still comfortable enough to showboat in the home straight.

He crossed in 8:10.07 to take 0.37 seconds off a four-year-old Games record set by compatriot Jonathan Ndiku at Glasgow four years ago. 

Abraham Kibwott took second place in 8:10.62 and Amos Kirui was third in 8:12.24 after overtaking a diving Matthew Hughes of Canada virtually on the line.

The only Paralympic medal event this evening saw Suwaibidu Galadima of Nigeria win the T47 100m. 

He shots out the blocks and never really looks like getting caught to win in 11.04 - 0.26 seconds ahead of England's James Arnott, who competes in the more heavily impaired T46 division but still gives him a good race to finish second in 11.30.

Tevaughn Thomas of Jamaica, also in the T46 category, was third in 11.63.