Catherina McKiernan's preparations for the Olympic Games in Sydney suffered a significant setback yesterday where she announced her withdrawal from the London Marathon on April 16th because of injury.

An MRI scan revealed that the damaged ankle, which forced McKiernan out of the FILA international race at Stormont last Saturday, was more serious than originally stated. It transpires that she fractured a small bone at the base of her ankle during a training run just days before the Belfast race.

It will keep her out of training for anything up to six weeks, causing a major revision of the spring programme she had devised with her coach, Joe Doonan, to ensure a smooth build-up to the Olympic Marathon in Australia.

Originally, it was thought she had merely sprained her ankle but it emerged yesterday that she had in fact suffered a green stick fracture. While not in itself serious, the timing of the mishap is potentially damaging to her Olympic schedule.

In spite of their disappointment, her handlers were attempting to put a brave face on the problem, stating that the big race in London is not in itself essential in ensuring that she arrives in Sydney in perfect condition for the task of winning a gold medal.

"It's a setback but nothing more than that," said a spokesman." Obviously she is disappointed that after putting in so much hard work over the last couple of months she is now being forced out of big races.

"That's a disappointment, for before she got injured last week, she felt she was in good enough condition to win the race in Belfast. But this time next year, we will hopefully be looking back as this break from competition as a plus rather than a minus.

"The most annoying aspect is that it will increase the myth that she has serious, on-going injury problems. This is not the case. She had her troubles in the early part of last year and didn't run particularly well in the Chicago marathon in October.

"But that wasn't down to a specific injury, more the general problems she experienced in the lead-up to the race. Since then, she has been running well in training, well enough to suggest that she was capable of going close to winning the London marathon for a second time in April."

In addition to the London event, she will also miss the Durham Grand Cross, a week on Saturday, when she was hoping to take on Paul Radcliffe in a repeat of her victory two years ago.

Having had to miss out on Belfast, McKiernan was looking forward to another big run in Durham but undeniably it is the lost opportunity of competing in London which will trouble her most in the coming weeks.

For one thing, the loss in earnings will be substantial. Precise details are not available but it is thought that she could have earned £150,000 by adding her name to those who have twice won the race. Coincidentally, she was also forced to pull out of last year's event because of an injury.

The other big consideration is that it deprives her of the opportunity of exorcising the ghosts of the ill fated Chicago race. Originally, London didn't figure in her plans for this year but after a flawed run in America had ended an imposing sequence of three marathon wins, it was felt that she needed a race in April to give her back her confidence.

Now she is to be deprived of that opportunity and it remains to be seen how it will impinge on her self belief which could scarcely have been higher after competing the third of her marathon wins and only just missing out on a world record in Amsterdam on November 1st, 1998.

As it happened, that race was to trigger many of the problems which threw her career off schedule in the months which followed. A foot injury which required minor surgery was the initial problem and after returning from warm weather training in Portugal, she announced that she was revising her programme.

It wasn't until the autumn that she finally distanced herself from her fitness problems and while neither her Chicago performance nor the cross-country race which followed in Brussels was particularly satisfactory, they had at least the merit of convincing her that she was once more physically strong.

To that extent, this newest blow is particularly discouraging and it remains to be seen how long it will take her to get back into competition again.

At this point, she is hoping to return to light training by the end of February and with luck, she could then be in a position to start running 10 kilometres road races and possibly half marathons in the summer.