- London 2012 - Swimming
Phelps signs off with Olympic gold No. 18
Michael Phelps signed off his career with his 18th Olympic gold medal as USA powered to relay gold on the final day of swimming in the Aquatics Centre.
Phelps, Matthew Grevers, Brendan Hansen and Nathan Adrian stormed to 4x100m medley gold in a time of 3:29.35 ahead of Japan and Australia, with Great Britain fourth.
For Phelps, who will retire after London 2012, it was a fitting end to a glittering career, the most decorated Olympian of all time securing his 22nd Olympic medal on his final competitive race.
USA, who have dominated in the pool, capped an impressive championships with a medley relay double as the women set a new world record of 3:52.05. Australia took silver, bronze went to Japan with Team GB finishing eighth.
Fran Halsall missed out on her first Olympic medal as she finished fifth in the 50m freestyle final - clocking 24.47 in a race won by Netherlands' Ranomi Kromowidjojo in an Olympic record time of 24.05.
Daniel Fogg finished eighth in the men's 1500m final as China's Sun Yan left his rivals trailing in his wake as he powered to victory in a new world record time of 14:31.02.
It concludes a disappointing championships for Team GB, who picked up just three medals from the swimming pool - Michael Jamieson's silver and two bronzes from Becky Adlington.