UCD student James Nolan coasted to victory in his first round heat of the 800 metres in the opening day of the World Junior Championships in Sydney yesterday, when he led the field home in a time of one minute 49.02 seconds and booked his place in the semi finals.

The Irishman took the lead after 120 metres and was only passed once when, as he moved down the back straight, Canadian runner Zach Whitmarsh make his break for home. Nolan reacted well to the challenge, though retaking the lead off the final bend and pulling away well to beat Britain's Tom Lerwill into second place.

Brian Liddy, meanwhile, fared less well in his 400 metre hurdles when, after a strong start, he tired in the home straight to finish seventh in a time of 53.49, almost a second and a half behind winner Angelo Taylor of the United States.

Ethiopian Assefa Mezgebu outsprinted Kenyan favourite David Chelule in the straight to win a thrilling 10,000 metres final. Mezgebu, last year's world junior cross country champion, tracked Chelule into the straight and surged clear to win in 28:27.79 from Chelule with Japan's Tetsuhiro Furuta third.

Mezgebu, who trains with Atlanta Olympic 10,000m gold medallist Haile Gebrselassie in Add is Ababa, was confident of victory as he sat on Chelule for most of the second half of the race. "Over the last three laps I knew I would win," said 18 year old Mezgebu. "It was not a hard race, not an easy one, medium I would say."

Chelule led from the 6,000m after Kenyan David Ngetich and Tanzanian Marko Hhawu bad set the early pace.

Nigerians dominated the opening rounds of the men's 100m sprints with Seun Ogunkoya claiming the fastest qualifying time into today's semi finals in 10.54 seconds, ahead of New Zealand's Dean Wise (10.66) and team mate Francis Obikwelu, the event favourite, who was easing up in his heat in 10.69.