Daegu (South Korea), Sep 4 (IANS): The Daegu world championships finally reached a thrilling peak, witnessing a world record falling in the last event with Usain Bolt's final run here Sunday seeing a Jamaican quartet extending its dominance in the 4x100 meters relay.

The defending Jamaican team, featuring Nesta Carter, Michael Frater, Yohan Blake and Usain Bolt, secured their lead in the first three legs thanks to 21-year-old Blake, the newly-crowned world champion in the men's 100m, Xinhua reported.

"For me, it was just to go out there fast. We did just that. I am proud of my team. I am happy with myself," Bolt told reporters after the event.

"I enjoyed being the anchor. I had a little problem with my Achilles. I can't run the bend.... Yohan Blake ran a great bend," he added.

Blake, who took the gold in the 100m final last Sunday in 9.92 seconds after Bolt was disqualified for a false start, ran the third bend leg.

After Blake passed on the relay baton to Bolt, the latter sprinted ahead in full charge, and crossed the finish line to a new world record of 37.04 seconds, six hundredths faster than their own previous record set in Beijing Olympics 2008.

The US, a traditional dominant force in the event, and Britain both failed to finish the race owing to failures in the baton change between the third and fourth legs.

France finished second in 38.20. St. Kitts and Nevis took the bronze in 38.49.

Despiting a surprising and sensational disqualification in the 100m final, the 25-year-old Bolt took home a 200m and a relay gold in his third World's appearance, making the most popular star here.

In the women's 4x100m relay, however, it was the US who gained the upper hand. The Americans snatched their sixth World's gold medal after clocking a year's leading mark of 41.56 seconds, the fastest in the World's in the past 14 years.

Defending champion Jamaica finished second, but still refreshed their national record with 41.70 seconds.

The bronze medal went to Ukraine, who clocked their season's best of 42.51 seconds.

Earlier in the morning session, Kenyan distance runner Abel Kirui retained his world title in the men's marathon after finishing the 42.195-kilometer race in two hours, seven minutes and 38 seconds, 2:28 minutes ahead the runner-up, which was the biggest margin in the World's history.

The 29-year-old thus owned the two fastest time in the World's history as he set a championships record of 2:06:54 in his debut in Berlin two years ago.

In the evening session, four athletes became world champions for the first time.

Somali-born British Mohamed Farah, 28, took gold in the men's 5,000m in 13 minutes and 23.36 seconds.

The US led the overall medals table with 12 golds, eight silvers and five bronzes. Russia came second with nine golds, four silvers and six bronzes. Kenya was third with 7-6-4, thanks to their distance specialists.

Jamaica, famous for its sprinters' speed, finished fourth with 4-4-1. However, the nine-medal haul is below expectations as the "fastest country of the world" was looking to win double-digit medals.

Jamaica was the second in Berlin with 13 medals, of which seven were golds.

The next IAAF World Championships will be held in Moscow in 2013.