The 27-year-old (pictured top) held off a strong challenge by China's Zhongrong Cao, who had to settle for silver, to win the third gold medal of these Games for the Czech Republic – and the country's first ever in modern pentathlon.

The much-fancied Russians, Aleksander Lesun and reigning Olympic champion Andrei Moiseev, finished just outside the medals.

"It's an amazing feeling," Svoboda said as he toasted his victory.

"I was thinking I could be on the top this morning – actually [I have] since my childhood – so it is the best moment in my sporting career.

"It was the best crowd I've ever seen so it was very nice."

Hungary's 2009 world champion, Adam Marosi, took bronze after a perfect 1,200 score in the equestrian event.

"This is the most important medal in my life," Marosi said.

Modern pentathlon gold medallist David Svoboda flanked by runner-up Zhongrong Cao (left) and Adam Marosi

"In the horse riding the clear round was an amazing feeling.

"This is my favourite event in the modern pentathlon and I'm very, very happy now."

Of Russia's surprising inability to secure a medal, Svoboda said he believed their athletes may have suffered from the national quotas which meant four or five talented Russians have been battling all year to qualify for one of the two places.

"I was concentrating for one race in the year, the Olympics," he said.

"That's the difference between me and my preparations, and the Russians' preparations."

Svoboda was cheered on by a noisy crowd of around 25,000 in the imposing arena at Greenwich Park as he led off the field for the combined running and shooting event, an innovation for this Olympiad along with the introduction of laser pistols.

"It's totally different," he explained.

"Now we are shooting very fast so we don't have to be really near by the ten.

"We were running together and he [Cao] was shooting nearby to me.

"I'm left-handed so I saw his mistakes and my mistakes, so it is mentally very hard.

"I was trying to be cool, calm down my mind – I was just focused on my shooting and it worked.

"I left the last shoot 50 metres behind Cao and from that point I was not going to settle for anything less than gold."

Reigning Olympic champion Andrei Moiseev finished without a medal at London 2012

Svoboda recalled how his chances of a medal in the Beijing Olympics had disappeared following a terrible time in the riding.

"That was the key event for me for success [this year] – it was a very sad moment for me four years ago," he said.

Svoboda, who had earlier equalled the Olympic record in the fencing, started the combined event with a one-second head start over Cao after faring better than his rival in the show jumping.

Cao's shooting was quicker than Svoboda's, but the Czech military officer was far stronger on the testing running course in Greenwich Park.

Marosi said he thought the combined event had improved the sport.

"For modern pentathlon when the rules changed it was very good because now the competition is very, very interesting and the positions change every time," he said.

"If you stay focused on the shooting area and just look at the target and listen in your heart and in your soul it's perfect."

Beijing Olympian Nick Woodbridge led Team GB's charge, finishing 10th amid huge support.

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