Radcliffe - gold medal performance (Getty Images).

Paula Radcliffe won Great Britain's only gold medal of the World Championships when she claimed a comprehensive victory in the marathon in Helsinki.

The 31-year-old produced an exemplary display of front-running after leading from start to finish and shaking off her rivals with a stunning injection of speed after the halfway point to set a new championship record of two hours 20 minutes 57 seconds.

Romanian Constantina Tomescu-Dita was the only athlete to offer any kind of challenge to Radcliffe but was blown away by the Briton's turn of pace and ended up being overtaken for second place by defending champion Catherine Ndereba of Kenya, who was more than a minute behind the winner.

It was a welcome contrast to Radcliffe's fortunes in Athens last year when she dropped out of both the marathon and the 10,000metres and also vindicated her decision to use the track race last Sunday, in which she finished ninth, as a final training run.

There was an added bonus when the team claimed third spot behind Kenya and Japan with Mara Yamauchi and Hayley Haining in 18th and 25th respectively although Debbie Mason did not finish.

Radcliffe said: "I am just really happy and happy the team took (World Cup) bronze. Very happy and very relieved. It was important. I knew I was in good shape and it was important to show that.

"It pretty much went according to plan. If somebody had been with me at the end I think I could have pushed it up a bit more.

"It is totally different to last year because I came in in good shape and with no health worries."

Radcliffe was in control of the race throughout and immediately stretched the field by imposing a testing pace.

"The idea was to go out at a pace that was decent but comfortable. I was feeling good on the hills and enjoyed them. They were not big hills so I felt very comfortable."

Prior to Radcliffe's gold, only the men's 4x100m team had secured a medal with bronze on Saturday night but she denied this had added any extra pressure.

"Not really," Radcliffe said. "The biggest pressure comes from myself because I knew I had worked really hard this year but had to go out there and prove it. It is very special."

Radcliffe made her intentions clear from the start, going straight to the front and imposing a quick pace.

She was joined by Yumiko Hara, of Japan, and Ethiopian Asha Gigi and the trio soon opened up a 20-metre lead over the chasing pack which included defending champion Ndereba.

The 31-year-old went through the five-kilometre mark in 16 minutes 47 seconds, three seconds ahead of Ndereba, who was beginning to stretch the pack, with Yamauchi the next Briton in 32nd place and the team in fifth.

Radcliffe maintained her three-second lead at the 10km mark over the chasing pack which was now down to just five runners including the likes of double Olympic 10,000m champion Derartu Tulu and Tomescu-Dita, as well as Ndereba.

It was the Romanian, renowned as an aggressive front runner, who broke to join the leading trio just prior to the 15km point with Hara being dropped soon after, swiftly followed by Gigi after almost an hour of the race with just Ndereba and fellow Kenyan Helen Kimutai within touching distance.

The Bedford athlete forged ahead and opened up a 20m lead just prior to the halfway point which she reached in 1hr 09.49mins - only 25 seconds slower than the fastest half-marathon of 2005 run by Ndereba.

With Radcliffe looking as if she was about to make a decisive break, Tomescu-Dita put in a spurt and caught the Briton with the pair holding a 20m lead over Ndereba.

However, after running shoulder to shoulder Radcliffe injected a stunning burst of speed after the 17-mile mark to impose a 20m lead with Ndereba a further 20m behind.

It effectively broke the Romanian who was then caught by Ndereba although the defending champion had not posed a threat at any point during the race.

Radcliffe raced away, looking fluid and in control, and continued to extend her lead until the finish line with Ndereba and Tomescu-Dita completely blown away.