LaShawn Merritt anchored the United States to a sixth successive world 4x400 metres relay title to bring down the curtain on the 15th world athletics championships on Sunday.

Merritt, who has been part of all six campaigns over the last decade, ran his leg in 44.16 to overhaul Jamaica’s Javon Francis on the final straight and cross the line for gold in two minutes 57.82 seconds, the best time of year.

Trinidad and Tobago, who led after the first three legs, won silver in a national record 2:58.20 and Britain pipped Jamaica to third place in 2.58.51.

Francis started the final leg at a searing pace to lead down the back straight but tired towards the end and was caught on the line by Britain’s Martyn Rooney.

Jamaica stun US

Jamaica stunned the United States in the last women’s track race of the world championships as Novlene Williams-Mills snatched the 4x400 metres relay gold by passing Francena McCorory in the final 10 metres of a thrilling race.

Jamaica had held a 15-metre lead over the United States at half-way, after strong runs by Christine Day and Shericka Jackson, only to see America’s individual 400m champion, Allyson Felix deliver an astonishing leg to chase down and catch Stephenie Ann McPherson and hand over the stick for the anchor leg with a slight lead.

Felix’s leg of the relay was timed unofficially at 47.7seconds but it was to prove in vain as Novlene Williams-Mills ran a shrewd final lap to overhaul a tiring Francena McCorory and win Jamaica’s third relay gold medal of the Beijing championships, and her nation’s seventh of the week.

Jamaica clocked 3minutes 19.13seconds, to the United States’ 3:19.44 with Britain taking bronze in 3:23.62.