The national champions put on a flawless performance to "Hometown Glory", posting a new personal best 153.81 points and totalling 231.99 to defend their world title.

"It was an out of body experience," said Duhamel.

"We knew we were better than what we’ve done this season.

"It was to come here and do it for ourselves.

"Back in October at the Grand Prix, I thought we were out of contention for a medal at the worlds.

"I thought we would be fighting for fourth or fifth.

"So what a turnaround we made, it feels so unbelievable."

Four Continents champions Wenjing Sui and Cong Han of China earned the silver medal with 224.47 points, while Germany’s Aljona Savchenko and Bruno Massot totalled 216.17 to capture bronze in their debut as a team at the World Championships.

Olympic gold medallists Tatiana Volosozhar and Maxim Trankov of Russia dropped from third to sixth as they made several errors, including on a lift that had no value.

In the ladies’ free skating competition, 16-year-old Russian Evgenia Medvedeva topped the podium with the United States’ Ashley Wagner climbing from fourth to claim silver.

Performing to the "W.E." soundtrack by Abel Korzeniowski, the European champion set a new highest score of 150.10 points, surpassing South Korean Yuna Kim’s 150.04 points from the Vancouver 2010 Winter Olympic Games.

"Right now I don’t have any emotions," said Medvedeva, the Grand Prix Final champion.  

"I left everything on the ice in my performance.

"I don't think I'll realise any time soon that I won.

"One year ago I was still skating in juniors."

Wagner, a three-time US champion, collected a personal best 142.23 points to give her 215.39 overall.

Russia’s Anna Pogorilaya, 17, was ranked fourth in the free skating and slipped from second to third with 213.69 points.

The US’s Gracie Gold, who had won the short programme, dropped to fourth after making two mistakes.

Competition will officially conclude in Boston tomorrow with an Exhibition Gala.