3 August 2012 Last updated at 12:02

Olympic athletics: Dai Greene wins 400m hurdles heat

World champion Dai Greene gets his quest for gold underway with a comfortable win in his 400m hurdles heat in London.

The 26-year-old eased home in 48.98 to book his place in the semi-finals.

Greene, Great Britain's athletics captain, says he enjoyed the noisy reception from the home crowd and it did not affect his focus.

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Watch the men's 400m hurdles heats in full here using the BBC's interactive video player.