Paula Radcliffe needs no reminding that in the past three years she has won two world cross-country silver medals and one for 10,000m on the track in Seville last summer when Gete Wami spoilt her gold medal ambitions.

Radcliffe makes no bones she has long wanted to add a senior success to the junior victory she achieved at the 1992 IAAF World Cross Country Championships. Certainly the sub-zero temperature and several inches of snow which existed in Boston on that occasion couldn’t compare with the humidity and heat of Veracruz on Sunday morning.

Conditions were just as harsh as both she and men’s race winner Paul Tergat predicted in the build-up to the 9th IAAF World Half Marathon Championships. But Radcliffe came properly prepared and duly achieved another ambitious step in her international athletics career.

Adapting to the Veracruz hotspot, Radcliffe, after cruising across the line in 1:09:07, admitted it had been as hard any road race she had contested, the intense heat and humidity troubling her just as much as every other contestant.

Indeed, mindful of the damage the Mexican Gulf temperatures could inflict, it was a mid-race touch of panic that spurred along Radcliffe, an asthma sufferer, who throughout the 21km contest was never outside the leading half dozen runners; second-placed Susan Chepkemei, Lidia Simon and Mizuki Noguchi being the other principal players.

Delighted to finish off her millenium season with a runaway victory - her time was restricted to exactly two minutes slower than the European record she set when winning the BUPA Great North Run three weeks ago - Radcliffe finished a huge 33 seconds in front of Chepkemei.

Kenya’s world cross-country bronze medallist herself held off Romania’s Olympic marathon runner-up Simon who clocked 70:24 as both suffered at Radcliffe’s unexpected but immediate response to a panic attack which forced a change to her race tactics.

The quartet remained together as 5km was navigated around the the magnificent Mexican seaport in 16:30 with Simon at the point of a 20-strong pack. By 10km (33:14) Radcliffe led the reduced field of four, then after 15km (49:41) took total control ahead of her quartet of challengers.

But it was a scary run for Europe’s recently crowned No.1. Before the start of the event, Radcliffe - who has suffered from asthma from childhood - taped her nose open with an elastoplast to allow herself to breathe more easily in coping with the intense heat and humid conditions around the 13.1-mile course.

Coming into the third and final 7km lap of the race, the tape fell away and a slight suggestion of panic went through the mind of the pre-race favourite. "I suddenly felt dizzy and I had to tell myself to keep calm," said Radcliffe. "As a result I just found myself going faster."

That injection of pace, with last year’s runner-up Noguchi also posing a threat, saw Radcliffe quickly drop the Japanese at eight miles with Simon surrrendering her gold medal interest just before 10 miles and Kepkemei shortly after that distance marker.

Although mastering the horrific heat with the breakfast time temperature almost 29C, Radcliffe - after effectively sewing up the race and looking a lonesome figure over the last three miles - crossed the finishing line admitting she had to work extremely hard for the winner’s US$40,000 purse.

As welcome as the money will be, Radcliffe admitted gaining her first ever senior world crown meant much more to her than the monetary reward.

"Ever since I won the junior gold medal in 1992, I’ve wanted to win a senior one," she said. "I’ve collected three silvers, two for cross country and the 10,000m one last year in Seville. I’m absolutely thrilled to have finished my season with my win here."

The last - and only other - Briton to have won the title was Liz McColgan, victor at the inaugural championships on Tyneside. "Liz has always been a hero and an inspiration to me," said Radcliffe. "She won her gold medal in the same year I won my junior cross-country one.

"I’ve always looked up to her and during my career I’ve tried to emulate her times and achievements. I’ve done that again and now I want to continue by winning the 10,000m on the track."

Over a course lined by a crowd of 25,000 excited spectators, Radcliffe said: "I’ve never ran on the roads in such an atmopshere. The crowd were brilliant. But they caused me a slight headache. I just couldn’t hear whether Susan and Lidia were coming back at me.

"They may have dropped behind, but it wasn’t an easy race and I didn’t know where they were. Running in those conditions was extremely hard. I took on as much water as I could and tried to keep cool by running in the shade when I could find it."

Team victory went to Romania whose trio recorded 3:34:22 ahead of Japan (3:36:25) and Russia (3:45:41).

David Martin for the IAAF