Turnbull was unable to respond to the leaders on the third lap

Belfast athlete Gareth Turnbull exited from the 1500 metres at the semi-final stage at the World Championships in Paris on Monday night.

Turnbull was well-placed for the opening two laps of his heat but he lost ground on the third lap and came in 10th out of the 11 competitors.

The Irishman clocked 3:42.01 which was just under four seconds behind the heat winner world record-holder Hicham El Guerrouj who won in 3:38.25.

Portugal's Rui Silva, Ukrainian Ivan Heshko, Spaniard Roberto Parra and Russian Vyacheslav Shabunin were the four other automatic qualifiers from the heat.

Turnbull is bound to gain from the experience of competing in his first senior outdoor championships and will now aim to ensure his participation in next year's Olympics in Athens.

Ireland's Karen Shinkins exited from the women's 400 metres on Monday evening.

Shinkins finished eighth and last in her semi-final in a race won by gold medal favourite Mexico's Ana Guevara.

The Irish woman clocked a disappointing 52.74 which was .68 of a second outside her season's best set in the first round.

Shinkins' personal best of 51.07 was set in 1999.

Sonia O'Sullivan competes in the 5000m heats on Tuesday

Derval O'Rourke suffered a somewhat chastening experience on her debut in a senior outdoor championship.

With the hurdler clearly still suffering the effects of the ankle injury she sustaining when finishing fourth at the European U23 Championships, she was eighth and last in her heat in 13.54.

That was more than half-a-second outside her personal best set at the U23 event in Poland.

What will disappoint the Irish woman even more is that a time of 13.28 would have been enough to have earned her a place in Tuesday's semi-finals.

Sonia O'Sullivan begins her 5000m challenge on Tuesday evening in the heats (1827 BST).

With the five first qualifying automatically from each of the two heats, O'Sullivan will need to run well as Olympic champion Gabriela Szabo and Sunday's 10,000m winner Berhane Adere will be in the qualifier.

Other athletes who could trouble O'Sullivan include Kenya's Isabella Ochichi, Russian Yelena Zadorozhnaya, Morocco's Zhor El Kamch and Germany's Irina Mikitenko and China's Huina Xing all of whom have all run under 15 minutes.

Meanwhile, Ballymena & Antrim sprinter Anna Boyle came through the opening two rounds to qualify for the 100m semi-final at the World Student Games in Korea.

Boyle clocked times of 11.91 and 11.95.