An ankle injury has forced Catherina McKiernan to make a late withdrawal from this afternoon's IAAF Grand Challenge International cross country race in the grounds of Stormont Castle, Belfast.

Her decision was only announced late yesterday evening, as she failed in her efforts to recover from the ankle strain suffered in training earlier in the week. McKiernan gave the injury every chance to heal, but when she underwent a last-minute fitness run late yesterday she decided it wasn't worth the risk.

"I was so geared up for this that it is very disappointing for me," she said. "Hopefully it won't be anything serious, but I just didn't want to risk it. I had hoped it would recover enough in time but unfortunately that wasn't so."

McKiernan first felt the injury late in a training run on Tuesday morning, but at the time believed it was only minor and wouldn't prevent her taking part in this afternoon's Belfast race, in which she would have been one of the main attractions.

The injury follows a succession of similar disappointments over the past 14 months, including the Achilles tendon injury which forced her withdrawal from the London marathon last spring.

The 29-year-old Cavan athlete had made a welcome return to cross country running just three weeks ago, finishing fifth in a high-quality race in Brussels. This afternoon's outing was set to mark only her second appearance as part of an Irish team since the 1996 Olympics in Atlanta.

There is now a question mark over her appearance at the Durham International cross country on the 22nd of this month, the next race that McKiernan had lined up as part of her preparations for another London marathon in April.

This news also comes as a major disappointment for the organisers in Belfast, who had billed this race as one of the best in the country in recent years.

Britain's Paula Radcliffe, who was the bronze medallist at the World Cross Country championships in Belfast last March, and the leading Ethiopian, Ayelech Worku, are just two of the high-class field, with a strong attraction being their planned clash with McKiernan.

Radcliffe is enjoying one of her best spells on the world stage. After finishing second in the World Cross Country Championships in each of the previous two years, she took the bronze medal in Belfast last year. It was in track competition, however, that she enjoyed some of her finest moments, producing British records at 3,000 and 5,000 metres before finishing second to her Belfast conqueror, Grete Wami of Ethiopia, in the world 10,000 metres championship in Seville.

Not surprisingly, perhaps, Worku could finish only fourth in the mud at Stormont 12 months ago but since then, she gained second place in the world 5,000 metres track championship in Seville. More recently, she was a full six seconds clear of McKiernan in claiming second spot in the World 8 km Cross race in Brussels.

For McKiernan the frustrations experienced for much of last year, including her disappointing run in the Chicago marathon last October, are set to continue for a few more weeks at least. All this comes at a time when she has stated that her training had been going well.

Meanwhile, visa problems were yesterday threatening the appearance of the favourite for the men's race, Patrick Ivuti of Kenya.

Carsten Jorgensen of Denmark, beaten only by Hendrik Ramaala and the Kenyan, Julius Chege, in last year's race, is an obvious threat to Ivuti if he runs, but unfortunately the Irish challenge is not nearly as strong as expected.

Seamus Power and Peter Matthews, the first two finishers in the National Intercounties Championship, left yesterday for training in Africa: Dermot Donnelly is recovering from flu and Gareth Turnbull prefers to concentrate on his preparations for indoor races.

It means that local man John Ferrin will now lead the Irish challenge and judged on his performance in the European Championship, he should run well enough to warrant the full support of the Belfast public.