ATHLETICS: At Pere Lachaise where they buried Jim Morrison you are reminded of those words, "this is the end", writes Ian O'Riordan in Paris.

Words that must sometimes be carefully used. It seemed like the end, though, for Sonia O'Sullivan when she left the Stade de France on Saturday after finishing a distant last in the World Championship 5,000 metres final.

But as hard as it is to explain her performance it is also hard to let those words stick. That she won't go out like this, not before trying once more to find the athlete who once conquered the world, and held the breath of a nation. For now, though, she is a beaten athlete. No one knows that more than O'Sullivan. She took an early flight out of Paris yesterday back to her London home, trying to make sense of it all.

The one race she had targeted all year. The race she truly believed she could influence and perhaps end as one of her greatest.

Even to watch it was as hard and as punishing a race as O'Sullivan's own experience. She'd been down this road before in Atlanta and Athens and New York but she'd never quite looked so lonely, or seemed so lost. Nor appeared so undeserving of such scaring. So finding her way back from this one as she heads towards her 34th birthday is the greatest challenge she's ever faced. Mentally more than physically.

She looked nervous at the start line, and truly crushed at the finish. After this her mindset might never be right again.

But it was a race, too, that no matter what way you look at it, not just from O'Sullivan's point of view, makes very little sense. Tirunesh Dibaba, an 18-year-old from Ethiopia and the new world champion, is about the only one of the 15 starters who got things right. How everything defied even the wildest predictions.

Since Saturday there have been several moments when O'Sullivan was in the position to offer some explanation, some possible pointer towards the moment she drifted behind the leaders, before they'd even gone halfway. But she couldn't. So she decided she wasn't going to explain it to anyone before she tries to explain it to herself.

Even when she was stuck in the moment, she had nothing to say. After crossing the line in 15 minutes, 36.62 seconds - the sort of time O'Sullivan has been known to warm up in - she simply removed her spikes and left them on the track. And started running.

She ran straight through to the mixed zone and after spying a few Irish faces twice hurdled four-foot barriers to avoid any contact. And to hide the tears. She collected maybe half of her gear and kept running out of the stadium. Running to try to stand still.

Yesterday after taking her to the airport her partner Nick Bideau was back for the final day's action in the Stade de France, and he tried to offer something.

"She just didn't have it out there," he said. "It just wasn't in her on the night. But perhaps she just couldn't take the two hard races so close together."

Her coach Alan Storey had also made brief contact, and offered this: "She just can't explain it. And I can't explain it either. But I know the same thing happened at the Atlanta Olympics, and she never really found out the reason why."

So much of Saturday's race was reminiscent of her nightmare in Atlanta seven years ago. The pace was slow and yet O'Sullivan was soon struggling, and after moving from the back to the front after 2,000 metres a trapdoor suddenly opened. And out she went. With seven of the 12 and half laps to go she was 10 metres adrift, and continued to lose ground from there to the end.

The leaders passed 3,000 metres in 9:08.88, normally pedestrian by O'Sullivan's standards, and yet there was no life in her legs. Dibaba won in 14:51.72, less than four seconds quicker than O'Sullivan had run in Tuesday's heat.

For O'Sullivan the immediate future is also unclear. She probably will compete in the Great Run series on the roads over the next few weeks, but her last great goal of the Athens Olympics next year has never seemed further away. Yet there were two small consolations for her yesterday. She was successfully elected onto the new IAAF Commission, and if she'd stayed around Paris she would have heard Edwin Moses, the former Olympic 400 metres hurdles champion, is planning a comeback for Athens. At aged 48. Could be plenty of time then to put the Paris memory behind her.