Lizzie Simmonds was an agonising fourth as 17-year-old Missy Franklin won the 200 metres backstroke in a new world record.
The 21-year-old was sixth in this event in Beijing and since then she has appeared in two world finals, coming fifth and seventh.
The Loughborough ITC swimmer was swimming from lane one after only qualifying in seventh, something she prefers rather than get caught up in a battle in the centre lanes.
Simmonds went out fast and was second at halfway, a pace she largely maintained and with 50m to go the Briton was third.
However, she was overtaken by American Elizabeth Beisel in the final 25m to be edged out of the medals in two minutes 07.26 seconds.
Franklin lowered Kirsty Coventry's world record set at the height of the shiny suit chaos in 2009 by 0.75secs to 2mins 04.06secs.