The biggest crash in a week of recurring mishaps for Irish athletes materialised yesterday when Mark Carroll went out of the men's 5,000 metres championship at the preliminary stage.

With the exception of Sonia O'Sullivan, none of the team travelled to Sydney with more realistic hope of competing in a final than the Corkman. But as his heat built to a sprint finish, that optimism was shown to be grossly inflated as he receded to seventh place in the last 600 metres.

For an athlete who has achieved so much this season, that was a huge disappointment. Even more frustrating, however, was the fact that in returning a time of 13 minutes 30.80 seconds, he was some 27 seconds outside his career best figures on a perfect evening for running.

Even allowing for the fundamental difference in grand prix and championship running, that was a staggering shortfall. And it would cost him the chance of going through as one of the three fastest losers.

After appearing to have called the shots right for the greater part of the journey, Carroll simply could not find the acceleration to go with the leaders when the searching questions were asked and this test of endurance was condensed into an exercise in speed.

"I think I got myself in the right positions throughout the race but when it came down to it I didn't have the snap to go and do it at the finish," he said.

"My race plan was to be well enough placed to wind it up over the last 600 metres and work off my strength. That's the way it's been for me most of the season but today it just wasn't there.

"This time it took me longer than normal to change gear 200 metres out and I cannot explain that. When I needed to quicken it took me too long to get going.

"That's what makes it all the more disappointing. The basics which have worked so well for me before coming to Australia simply didn't function out there."

The pattern of the race was simple enough. After just four laps, the Moroccan, Said Mohammad El Wardi, bolted like a startled hare and within a matter of 100 metres was well clear. The equation then for some of those in his wake was whether to go after him and risk early burn-out or stay in the relative security of the pack.

Carroll chose the second option and, reflecting on the race, said: "I almost regret not going with the Moroccan. But I just figured at that point he was going so fast it was not worth the gamble.

"I sat back in again, felt fine and was full of confidence going into the last 600 metres. Even against these guys I'm always able to kick down. In grand prix races I am blowing by most of them every time - but not here.

"I didn't get firing all out until the finishing straight. But then it was too late and I just ran out of track."

The Irishman can scarcely have been unaware of the growing urgency of his predicament. The first heat had been won by the Moroccan, Brahim Lahlafi, in 13 minutes 22.70 seconds and by the middle stages of the second it was already apparent that the fastest losers would come out of that race.

But still the chasing group refused to go after the runaway leader with any conviction. Instead, they decided to wage a war of attrition among themselves, testing each other out in short, sharp bursts.

In the mistaken belief that he had the finishing pace to cope, Carroll was content to stay where he was, covering every break so diligently that he was always in contact with the leaders. It was against that background that he couldn't rationalise his late collapse when the chips went down approaching the bell.

Before they had reached the entrance to the back straight, he had crucially lost two places in the jostle for position. And by the time he worked up to top pace, there was sadly no way back for him.

Carroll was not the only unexpected casualty, for Venusto Nyongabo, the reigning champion, trundled home in 15th place, a mere shadow of the athlete who had dominated his opposition so impressively in Atlanta.

Not surprisingly, perhaps, El Wardi was reined in when the big names at last decided to open up on all cylinders. And none was more impressive than the Algerian, Ali Saidi-Sief, who exploded into action on the last lap to win from Sergiy Lebid of the Ukraine and Dagne Alemu of Ethiopia in 13:29.24.

Africa's dominance was even more pronounced in the other heat in which they filled the top six places with Lahlafi producing a stunning late burst to win narrowly from Ethiopia's Millon Woldi.

It had been another chastening day for Irish athletes - apart from O'Sullivan - and for Carroll in particular the memories of a bitterly disappointing run will not easily go away.