Double bid ruled out by Radcliffe.
World record-holder Paula Radcliffe has confirmed she will not contest both the marathon and 10,000 metres at this summer's Olympic Games.
Radcliffe, who gained the 10k track qualification standard with a world-class victory of 30 minutes 17.15 seconds in Gateshead, admitted the task was even beyond her powers.
"I am now qualified for both the marathon and 10k but it is impossible to do both," she said.
But Radcliffe, who was racing on a British track for the first time since winning the Commonwealth 5,000 metres title in August 2002, said: "It is a very nice to have the option."
The 10,000m European champion went through the motions of beating the 31mins 45secs qualifier in yesterday's Norwich Union Grand Prix. Before the race she had revealed she had ambitions of breaking her personal best of 31 minutes 1.09 seconds which won her the European title 22 months ago in Munich.
At the half distance, she was still in with a chance of lowering her European mark ( the second fastest of all-time behind Wang Junxia's world record 29mins 31.78secs ( but lack of opposition and a drop in the temperature at the Tyneside venue ruined any hopes when she was left to cover the last eight kilometres on her own.
Radcliffe, who ran the quickest time in the world this year, said: "I wanted to run faster and naturally I'm disappointed."
Last Sunday she ran her first race of the summer after undergoing a hernia operation in March and set a European and Commonwealth 5,000m record when clinching the European Cup title in Poland. "I've now done two good races and I'm looking forward to the Olympics," said Radcliffe. "I only ran here to keep my options open."
Radcliffe was dismayed Russian pacemaker Yuliya Kosenkova did not go to the half-distance. "It was warm and everything was okay in the early stages. It wasn't too bad but when the wind changed direction, I knew then it was a tall order, especially when the pacemaker dropped out at 2k, when she looked okay to me."
Radcliffe specifically chose to compete in Gateshead, where she has a marvellous relationship with the region's supporters.
In the past, particularly in last year's BUPA Great North Run, where she ran the quickest half marathon in history, they have given unmatchable backing.
"It's a shame ( the only 10k in this country and the conditions were against me," said Radcliffe.
"I was helped by the crowd, who counteracted me running on own."
Radcliffe will shortly return to her training base in the French Pyrenees but will have another race either on the track or the roads before the Olympics.
But while Radcliffe was in majestic form, former Olympic champion Fernanda Ribeiro finished a distant second in 31mins 32.28secs and Latvia's Yelena Prokopcuka, who clocked 31mins 42.91secs, while Hayley Yelling missed the qualifying standard.
For Yelling it was her third attempt to make the required target but, after failing by a mere 0.14secs in Watford earlier this month, she was again short of the mark, finishing fifth in 32mins 00.43secs.
One record which was smashed came in the pole vault where Yelena Isinbayeva raised her own world mark to a massive 4.87 metres.
It was the fifth time the Russian has bettered the record ( indoors and outdoors ( although there is now no differentiation between the two made by the International Association of Athletic Federations.
She beat Russian arch-rival Svetlana Feofanova, who cleared a season's-best of 4.70m, and afterwards said: "I am now ready to jump higher but I want to do it step-by-step, centimetre by centimetre.
"I will be back to do five metres," forecast Isinbayeva. "I like Gateshead, I broke my first record here last year and I've come back and done it again."
Exciting Ethiopian talent Kenenisa Bekele may have, in the last month, broken both the world 5,000m and 10,000m records but failed to smash the 30-year-old stadium record set by British running legend Brendan Foster 30 years ago.
At the opening of the Gateshead Stadium, Foster ran 7mins 35.10secs and it seemed his record was certain to fall into the hands of Bekele.
Bekele, on his own after less than four laps, was initially well on target but slowed to 7mins 41.31secs, well clear of Kenya's Paul Bitok (7mins 50.54secs) and Craig Mottram from Australia (7mins 50.64secs).
Individual British victories came from Chris Lambert, who defeated British 200metres number one Christian Malcolm by 0.07secs in 20.57secs.
There was also a brilliant victory in the 400m hurdles by Chris Rawlinson, who won by almost 20 metres from Nick Stewart.
Last weekend's European Cup champion clocked a season's best of 48.58secs, with the Canadian finishing in 50.17secs.
"I've changed my stride pattern this year and that has made a big difference," said Rawlinson, who was delighted to learn only former world record-holder Ed Moses has ever run quicker on the Gateshead track.
Carl Myerscough won the shot-putt with a best effort of 20.85m but his drug suspension four years ago will bar him from the Olympics.
Kelly Holmes registered her first win of the summer in the 1,500m in a time of 4mins 6.83secs ( her first success in three races this summer.
In a slow race, Holmes ran the first 500 metres at the back of the field before gradually moving through the pack into an attacking position. The Commonwealth champion powered into the lead coming into the home straight to win from Poland's Lidia Chojecka (4:07.73) and fellow Briton Helen Clitheroe (4:08.47).
"That was okay, I just ran my sort of race," said Holmes. "I like it tactical, I am still not too sure of myself at the moment."
Holmes, who only returned from competing in the USA earlier in the week, added: "I have still got to find my racing brain."