Martyn Rooney guides Great Britain to 4x400m relay silver
It brings Britain's medal total to six - beating the target of five set by UK Athletics head coach Charles van Commenee, that even he claimed was optimistic after a championship build-up punctuated by injuries to podium hopefuls.
United States - with a powerful quartet that included both LaShawn Merritt and Jeremy Wariner - predictably galloped clear to gold while Martyn Rooney on Britain's anchor leg tenaciously held off Australia to claim second.
Conrad Williams and 400m finalist Michael Bingham had given Britain a flying start and they were comfortably the best of the rest for most of the race.
Rob Tobin temporarily lost that advantage during the third leg but brought it home strongly to Olympic finalist Rooney, who was determined to salvage something from a season ruined by injury.
"I'm still not as fit as I'd want to be but I've got a silver medal so I'm happy - it was just amazing," Rooney explained.
"But with about 100m to go I thought ‘no one is going to get past me now, I've got it'. I'm a good chaser but didn't need that out there. I had a nice clear run which was great.
"The other guys set it up for me and I had the easy job of just finishing it off. I was really confident from the moment I picked up the baton."
But there was disappointment for Great Britain's 4x400m women - who missed out on a medal after winning bronze in both Helsinki and Osaka.
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Olympic champion Christine Ohuruogu was drafted back into the line-up at the expense of 800m bronze medallist Jenny Meadows, who ran in last night's heat.
However, along with Lee McConnell, Vicky Barr and Nicola Sanders, she was never in touch with the top three.
World champions Sanya Richards and Allyson Felix inspired America to victory as they topped the medal table with ten golds, while Jamaica and Russia completed the podium.
American Brittney Reese won the women's long jump with a world leading 7.10 metre leap while Russia's Tayana Lebedeva took silver and Turkey's Karin Mey Melis claimed bronze.
Norway's Andrea Thorkildsen won the men's javelin with a season's best 89.59m, with Cuba's Guillermo Martinez three metres behind and Japan's Yukifumi Murakami in third.
And following Caster Semenya's victory in the women's 800m, South African team-mate Mbulaeni Mulaudzi completed the double to take the men's gold - although his win lacked the controversy.
Kenya's Alfred Yego and Bahrain's Yusuf Saad Kamel settled for the minor medals in a blanket finish.
