Sonia O'Sullivan is back in the world of top-class athletics again after a superb run took her to within a fraction of a second of winning the Olympic 5,000 metres championship in Sydney yesterday.

Twenty-three hundredths of a second, precisely, was the difference between gold and silver at the end of an enthralling duel all the way down the finish straight with world champion Gabriela Szabo.

Both women went under 60 seconds for the final 400 metres to give Szabo a new Olympic record of 14 minutes 40.79 seconds, with O'Sullivan claiming a national record of 14.41.02.

Not since 1995 had the Irishwoman gone anywhere close to those figures, a yawning gap which straddled the personal disaster of Atlanta four years ago, the deepest crisis of a captivating career. Now, credibility has been fully restored and it showed as she prepared to walk to the presentation podium for another honour to set beside her World and European Championship honours.

"This has exorcised the ghosts of Atlanta," she said. "That was like a nightmare, this is like a dream. I feel now as if Atlanta never existed."

Silver was more than many expected. And yet, it was so very nearly a triumph to rate with Ronnie Delany's heroics on the last occasion the Games were held in Australia in 1956.

After detaching herself from the chasing pack to go after Szabo down the back straight, O'Sullivan appeared to have the race at her mercy when she moved onto the Romanian's shoulder rounding the last curve.

At that point, she looked to be all over Szabo, accentuating the physical difference between the tallest and one of the smallest athletes in the race. Surely the leader, we thought, couldn't summon either the courage or the strength to fight off the woman who had beaten her in the European Championships two years ago.

But Szabo has never been short on bravery and even as the last vestige of strength emptied from her legs, she somehow found the means to protect her precious lead to the finish line.

"Coming off the last bend, I definitely thought I was going to win," said O'Sullivan. "I mean I felt that little bit stronger, I felt bigger, I felt better than Szabo. But in the end she had that little extra inch on me."

The feeling that O'Sullivan was about to prevail was shared by most of us as we sat on the edge of our seats and watched the drama unfold in front of us. And yet there was a point in the race when it looked as if the demons of Atlanta in 1996 had come back to haunt the Irishwoman.

After running quite comfortably in the opening three laps, O'Sullivan suddenly dropped off the pace on the fourth circuit to drift back to 11th place. That was just as alarming as the monumental mishap in Atlanta and it showed in her face.

"There were points in it (the third lap) when I don't remember what happened, what was going on, or what I was thinking at the time," said O'Sullivan.

"It was a weird feeling. There was nothing in my mind at that point - just emptiness. You're in a state of `I'm here - what'll I do'. There was no time to think but, deep down, I knew that I couldn't afford to let it go as easily as that.

"The only way back was to work hard - and I did. But I'm still trying to figure what went wrong at that point. "A lot of it could be down to confidence. I have been away from big races like this for a long time. You can run grand prix races all your life but they're not like the World Championships or the Olympics.

"There is a thin line between running well and struggling, but whatever it is, I've got it back now. I'm now ready to go after it again. I believe I'm definitely back to where I was and now I just want to go out and get after it.

"There were moments when it was quite hard. And there were moments when it was nearly taken away from me. But I got it back and that's a good feeling."

To her great credit, O'Sullivan looked disaster in the eye and found the character to become competitive again. Gete Wami's sudden change of pace had been responsible for her problems, but when the Ethiopian slowed it down two laps later, O'Sullivan had become fully competitive again.

Before the race, the great fear was that the three Ethiopians - Wami, Ayelech Worku, who eventually finished fourth to Wami's third, and Worknese Kidane, the youngest member of the trio - would work as a team to demoralise the opposition. But, happily, there was a late change of plan. "We talked about it earlier in the day and decided that in fairness to ourselves and the importance of the race we would run as individuals and see how it went," said Wami.

"I don't think it affected our chances. It was a very hard race but after running at the front for so long I didn't have anything left for the last 400 metres."

O'Sullivan later confessed that she had identified Wami rather than Szabo as the main threat. "After all, she had run faster than any of us this season, but when it came to the crunch, she wasn't brave enough."

No such criticism could be levelled at Szabo. She was at the cutting edge throughout, taking on the three Ethiopians and the two Kenyans, Lydia Cheromei and Rose Cheruiyot, in a manner which suggested that irrespective of the price of gold on the day she was ready to pay it.

Skimming across the track with characteristic economy of movement, she was always in a position to cover the breaks, never more so than on the second last lap when, in a last desperate attempt to break her rivals, Wami dipped into the reserve fuel tank to put distance between herself and those who imperiled her ambition of winning gold.

Soon, very soon, she realised that the reserves had run dry and shortly after the bell for the final lap she retreated from the front line to leave the stage and the final exhilarating moments to the two Europeans.

Mindful of how O'Sullivan out-kicked her to win the European title in Budapest, Szabo put her courage on the line and went for broke from 200 metres out.

At one point she was a good two metres clear, but then as O'Sullivan jutted her jaw and gave chase, the lead began to dwindle centimetre by centimetre. The prospect of a famous win opened up for the hundreds of Irish supporters in the stadium and the thousands of Australians ready to roar home an adopted daughter.

Sadly, it was not to be, but in defeat O'Sullivan could console herself in the thought that hers had been an enormous input into a race which was never less than fascinating.

Not the least surprising aspect was the time which, off a mundane early pace, was little short of astonishing. "I couldn't believe it when I looked up and saw 14.40 on the scoreboard," O'Sullivan said. "I thought to myself `How did we run that fast, were we a lap short or something'. It shows that I just have to be a little braver and I'll be great."

That last comment was quite superfluous on the day. The gold medal may have got away, but in every other respect O'Sullivan was a champion on the day.

Now for the 10,000 metres!