On a night which, after two narrow semi-final defeats, brought more frustration for the Russian hosts, the men's under 74kg gold was taken by Masoud Hajizavareh to continue Iranian domination of the two male categories completed here so far. 

But it was Ha who provided the highlight on the second day of finals action by holding her nerve in a golden point period against a vastly more experienced rival.

To make the final she first had to overcome a tough opponent in Serbia's Tijana Bogdanovic, 7-5, in a fight which sparked into life after an explosive last round in which, despite being on the back foot, Ha excelled by picking off successive points with well-aimed counter-kicks.

The final, against the Beijing 2008 and London 2012 Olympic champion who also won world titles in 2007 and 2011, was always likely to be a tougher affair. 

But, while many expected Wu to romp to victory, from the moment Ha snatched a point within seconds of the bout getting underway, it was always a closer and cagier affair.

The Chinese player, who also won bronze at last year's Asian Games in the heavier under 53kg division, fought back to take a 3-1 heading into the final round and, with Ha visibly tiring, victory appeared hers once again.

Yet, following a pause for a speculative and unsuccessful video replay attempt from her coach which may have been more a tactical ploy to give her time to recover, the South Korean appeared reborn in the final 20 seconds, reducing the arrears by one before striking again with just three seconds left.

This ensured a golden point period and with the momentum now in her favour, it was Ha who struck first, scoring with a perfectly-placed right-footed kick after a flurry of attempted blows - surprisingly left unchallenged by the Chinese coach - to become the first South Korean to win the world title in the under 49kg event since it was first introduced at the 2009 edition in Copenhagen.

Bogdanovic and Russia's European bronze medallist Svetlana Igumenova, who was well beaten by Wu in the opening semi-final of the evening, took the two bronze medals. 

At this point, all three gold medals won at the Championships had been taken by those aged 18 or younger, but this was to change in the men's event as the final pitted a 26-year-old Iranian against 21-year-old Nikita Rafalovich from Uzbekistan, who had reached the final by a last gasp head shot to snatch a 4-3 victory over Mali's Ismael Coulibaly.

Hajizaverah, who had been pushed just as close in his semi-final after requiring an extra period to defeat home hope Albert Gaun, was the favourite going into the final, and, showed just why in the first round with a beautiful head-kick to take a three-point lead.

There was more of the same in the second after a second such head-kick late in the period powered him to 8-2 ahead.

But to his credit the Uzbekistan fighter refused to give up, and despite some clever tactical play from the Iranian - first pulling his opponent close to give him no room to strike and then repeatedly retreating off the mat and out of range - the gap was reduced to 9-7 with 10 seconds left.

That was as close as it got however, and with Rafalovich sinking to his knees, Hajizaverah leapt in the air in celebration before clutching the Iranian flag for a well-deserved lap of honour.

There will be no hatrick tomorrow as no Iranian qualified for the semi-finals of the men's under 68kg division, but, after making it through, the home crowd will be hoping Alexey Denisenko can make it fourth time lucky and become the first Russian to qualify for a final; something bound to turn a good atmosphere here into a great one.

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