INJURY has forced Alison Curbishley to abandon plans to switch to the 400 metres hurdles this year - the event at which Colin Jackson had predicted she would win the European and Commonwealth titles this summer, the world crown next year, and the Olympics in 2000.

World Student and European junior champion at the flat 400m, Curbishley, from Edinburgh Woollen Mill, was Scotland's most successful athlete last year, also reaching the semi-finals at the world championships.

''I've been plagued with a knee injury for the past couple of months, and it is aggravated by hurdling,'' she said. ''I am pain-free running on the flat - it only surfaces when I hurdle, but afterwards I would only be able to train easily for four or five days.

''I could keep trying, and have it ruin my season, or decide to concentrate. My priority was to get through the season well, not have a mediocre one, so I've pushed the hurdle switch back for as long as it takes - the end of the season, but maybe not until next year. I hope to run the 400m at the European Cup later this month in St Petersburg.''

Curbishley's first two races this season have been encouraging, 51.45 and 51.35: ''a lot faster than I expected to start,'' but she steps up to a more significant level tomorrow when she runs over one lap in Milan. A 200m race follows in Dortmund on Sunday.

This means Curbishley, like Ian Mackie, will be unavailable to Scotland for the Home Countries international at Leeds on Sunday. Mackie contests his first major 100m of the year in Germany, and says: ''I think I am in shape to go below 10.20 if conditions are right.''

However, his future development will be without Pitreavie coach John Macdonald, who has looked after the Fifer since he was 12. Macdonald, father of the former international sprinter Linsey, confirmed yesterday that he has declined to coach the Olympic semi-finallist any longer. ''Ian's decision not to run the relay for Scotland at the Commonwealths is part of the reason, but there is more to it which I do not wish to go into.''

Jackson, meanwhile, has abandoned plans for his long jump debut tomorrow. The event in Milan has been cancelled, and he will hurdle there instead.

There promises to be an excellent celebrity turn-out at Leeds, with triple jumper Jonathan Edwards beginning his outdoor season, and javelin pair Steve Backley and Mick Hill.

Scottish triple jumper Stuart Richmond, with a legal best of 15.27m, more than three metres behind Edwards' world record, should reflect how far Edwards has come since his only Scottish title 13 years ago with 15.09m, while Border javelin man Sam Armstrong will simply have to live up to his name.

q GRAMPIAN Enterprise have agreed in principle to negotiations with Brendan Foster's company, Nova, which could involve them in #175,000 expenditure to bring the Balmoral Challenge road races back to Royal Deeside next year.