Earlier, Alistair Brownlee from Leeds won the under-23 category which, following the victory on Thursday of Kirsty McWilliam in the junior women's race, meant Britain finished top of the medals table.

 

Tucker, a 25-year-old from Bridgend, won as defending champion, Portugal ’s Vanessa Fernandes, could only manage tenth.

 

Tucker, who met the British Triathlon Olympic selection criteria two weeks ago in Madrid, was part of a British and American driven breakaway which included the heavy favourite, Fernandes.

 

However she and Sarah Haskins of the United States drove off the front of the bike pack to establish an unassailable two minute lead by second transition as the British women controlled the chasing pack allowing the pair to escape.

 

Having run side by side for 9.9km, Tucker then unleashed a strong kick to out-sprint Haskins as she crossed the line in a state of disbelief and elation.

 

Further back New Zealand ’s Samantha Warriner pipped Australia ’s Erin Densham for bronze.

 

"Vancouver is my new favourite place," said a delighted Tucker, shortly after crossing the finish line in two hours, one minute and 37 seconds, four seconds ahead of Haskins.

 

"It's not going to sink in for a few days.

 

"I wasn't planning on coming to worlds; it was kind of a last-minute decision.

 

"I'm glad I did now.

 

"The cold weather definitely made it harder, coming out of the swim my feet were really numb and tiredness started to set in a lot quicker on the bike.”

 

Tucker becomes only the second British woman to win the World Championships after Leanda Cave won in Cancun , Mexico , in 2003.

 

Her victory marks an exceptional return to form following two injury plagued years.

 

Brownlee won as he dominated the field amidst wet conditions, coasting to the finish line draped in the Yorkshire white rose flag.

 

The 20-year-old, whose brother Jonathan took bronze in the junior men’s race on Thursday, finished third at the Madrid BG Triathlon World Cup a fortnight ago to meet British Triathlon’s Olympic selection criteria.

 

The Brownlees are the first brothers in history to medal at the same triathlon World Championships.

 

Brownlee also becomes just the second triathlete in International Triathlon Union history to win both junior and under-23 world titles.

 

Last year's under-23 world champion, Gregor Buchholz of Germany, showed off his strong finishing kick to edge out New Zealand's Martin Van Barneveld for the silver.
 
"I'm absolutely delighted, it's brilliant to be world champion again," said Brownlee, who won the junior World Championships in Lausanne in 2006.

 

Britain ’s Todd Leckie also finished fourth, just outside the medals on his World Championships debut.

 

In the senior men's senior race Spain's Javier Gomez finished 24 seconds ahead of 2004 Olympics silver medallist Bevan Docherty of New Zealand, with Switzerland's Reto Hug third.

 

Britain's Oliver Freeman, who will not be going to the Olympics, finished down in 15th place.

 

Picture @ Delly Carr and triathlon.org