Abughaush, who secured his country's first-ever Olympic medal at Rio 2016 when he claimed gold, secured victory thanks to a two-point score with less than three seconds remaining in golden point.

It followed a 5-5 draw in regulation time during which Sinden, an under 63kg bronze medallist at the 2017 World Championships in Muju in South Korea, twice led.

The Briton had earlier defeated top-seeded Belgian Jaouad Achab in the quarter-finals.

"The gold could have been mine but for the last few seconds," Sinden said.

"However, it’s all a learning curve and I know I produced some really good performances."

The bronze medallists were Spain’s Joel González Bonilla, the 58kg Olympic champion at London 2012 and two-time world champion, and Russia’s Alexey Denisenko, who lost 19-17 to Abughaush in the semi-finals in a repeat of the Rio 2016 final.

Disappointment soon turned to joy for Britain as 2016 European champion Lauren Williams overcame Ivory Coast’s Ruth Gbagbi 43-23 in the women’s under 67kg final.

The double junior world champion trailed 15-13 after a frantic first period, but after taking a 16-15 lead early in the second, she never looked back.

Gbagbi, the reigning women’s under 62kg world champion, tried all she could to force her way back into the contest to no avail.

Williams' route to the final included a hard-fought success over world champion Nur Tatar of Turkey in the last eight.  

It was followed by a 32-26 semi-final win at the expense of the United States' Paige McPherson, a London 2012 bronze medallist.

"This means so much to me because it is such a big competition," the 18-year-old Williams, who was making only her second Grand Prix appearance, said.

"I beat some top girls along the way and I am lost for words to be honest.

"I was on it all day and that’s the first time, I think, I have enjoyed a competition. 

"What worked for me was I didn’t put any of the other girls above me.

"I just focused on my own game plan and it worked."

McPherson and Croatia’s Matea Jelić rounded out the podium.

The last final of the evening saw South Korea’s In Kyo-Don beat Russia’s Rafail Aiukaev to secure the men’s over 80kg crown.

Having quickly established a 2-0 lead, In went onto preserve his advantage throughout and ultimately triumphed 15-8.

He had earlier claimed a narrow semi-final win over Iran’s Sajjad Mardani, who shared the third step of the podium with Britain’s Mahama Cho.

Top seed Abdoul Issoufou of Niger, the Rio 2016 silver medallist, lost to Aiukaev in the second round.

All three of today's winners will automatically qualify for the newly-established World Taekwondo Grand Slam Champions Series, which is due to take place in Chinese city Wuxi from the end of this year to early 2018.

The spectators who witnessed their victories were assisted by the "Power Bar", which was introduced by World Taekwondo for the first time as part of the governing body's commitment to enhancing fan engagement and making the sport easier to understand. 

The "Power Bar" provided fans with a visual representation of the strength of the athletes’ strikes, allowing them to understand why some strikes registered points and others did not.

A moment's silence was held prior to today's semi-finals and finals in honour of Kim Un-yong, the founding President of World Taekwondo.

Kim died earlier this month at the age of 86.