ATHLETICS:It would be exaggerating a little to describe Sonia O'Sullivan and Paula Radcliffe as the greatest of rivals, and yet somehow their running careers became inexorably intertwined. Given their four-year age difference they probably never clashed at the peak of their careers, and in reality O'Sullivan was much more of a track specialist, while Radcliffe lapped up the country and roads.

There were several so-called showdowns, probably starting with the European 10,000 metres in Budapest in 1998. O'Sullivan was running the distance for the first time, and won brilliantly, while Radcliffe, having made some of the early pace, ended up fifth.

Two years later, in the Olympic 10,000 metres in Sydney, they shared that most memorable moment. Radcliffe had run to the point of collapse to finish fourth, and when O'Sullivan finished just behind her in sixth she helped the British athlete up from the track and back to her feet.

That was made easier in that O'Sullivan had already pocketed the silver medal from the 5,000 metres, but it was a symbolic as much as a sporting gesture - and the reason why their careers will be forever associated.

While O'Sullivan became the subject of massive fascination for Irish athletics, Radcliffe became likewise for Britain.

Just as both athletes were capable of dominating a championship race, so too were they capable of a spectacular collapse, normally more severe in O'Sullivan's case, while for Radcliffe that typically meant finishing fourth.

So even those with only a passing interest in the sport would mull for hours over how they looked in races, the distance they'd chosen or the tactics they'd adopted, and then wonder out loud if they'd made the right choice. And nowhere was this fascination greater that at the 2004 Olympics in Athens, when, almost by fate, neither of them claimed the elusive Olympic gold medal they so desperately craved.

The sight of O'Sullivan trailing off in the 5,000 metres and of Radcliffe dropping out of the marathon will inevitably feature as part of their epitaph.

Given this background we shouldn't be at all surprised that both of them are running this weekend with the Beijing Olympics in mind. For Radcliffe, who turns 34 in December, the dream of winning that gold medal is very much alive, and no one realises that more than herself. For O'Sullivan, who turns 38 in November, that dream is as good as over, and again no one realises that more than herself.

In another curious way Radcliffe finds herself in territory O'Sullivan would be well familiar with. When Radcliffe lines up for tomorrow's Great North Run in Newcastle it will be her first race in 21 months, the long-lay off mainly explained by the birth of her first child, daughter Isla, last January. She also endured injury complications arising from that birth, which at one stage threatened her career, and it's been a slow and difficult road back to full fitness.

Radcliffe's meticulous and exhaustive preparation for races ensures she rarely goes to the start line unless she's sure of winning, and that should be the case in Newcastle. Then the real journey to Beijing begins, as Radcliffe must first run the marathon distance to qualify, and then deal with all the unavoidable hype and pressure surrounding her quest for that elusive Olympic medal, of any colour. O'Sullivan, who gave birth to her first daughter the year before the Sydney Olympics, also began her comeback in Newcastle.

"I have no time in mind for Sunday, and as yet no plans about where I will race next," says Radcliffe. "That will all depend on how things go. It's hard to judge from my training what shape I'm in, but I chose the Great North Run because it's an important race, and I always run well in it."

O'Sullivan's appearance in tomorrow's Berlin Marathon hasn't attracted as much fanfare, and understandably so. Earlier this year she announced her retirement, even if that proved something of a false finish.

O'Sullivan in fact had no intention of retiring on the spot, and instead mapped out a few final goals of her career - her "last lap" - one of which was to run another marathon. Given Berlin's famously fast course it was the obvious choice, and that Olympic qualifying standard of 2:37 will unquestionably be her target.

This time last year she ran 2:42 in the New York marathon, with limited preparation, and for tomorrow's race she has employed the pace-sharing services of Australia's Craig Mottram.

"I have been doing a lot of long runs but have not done any sessions and have no idea what my form is like," says O'Sullivan. "That (2.37) is six-minute mile pace, and I feel that is possible. But if I do get it then I will obviously sit down and consider what I will do. I am not saying I would go to the Olympics, or anything like that. There is so much involved."

Needless to say Radcliffe's chances of running the Beijing Olympic marathon are immeasurably better than O'Sullivan's, but who could deny both of them being there, sharing one last moment, and bookending their Olympic careers the way Baron de Coubertin would have seen fit?