A fighting performance saw the British men's 4x400 metres relay team make progress when placing second to Jamaica in their heat.

But the squad are under no illusions about how difficult it will be to emulate the the silver medal they won behind the United States four years ago in Atlanta.

The British quartet of Jared Deacon, Daniel Caines, Jamie Baulch and Iwan Thomas clocked 3:04.35 to hold off France by one hundredth of a second and clinch one of the two automatic qualifying places.

Thomas said: "It's going to be tough. We haven't got the strength in depth we had in the squad four years ago.

"We'll be going flat out for a medal but judging by this every race is going to be a final and we're going to have to field our best team in every race."

Baulch: "I think we got one of the hardest heats but it was nice to get in the first two and qualify. We blew away a few of the cobwebs, so it was good."