Rio Olympics 2016: Jazz Carlin through to Olympic final as Guy and Proud make semi-finals
Great Britain's Jazz Carlin qualified for the Friday's 800m freestyle final as she finished third in her heat.
The Rio 400m freestyle silver medallist, 25, finished in eight minutes, 19.7 seconds.
Compatriots James Guy, 20, and Ben Proud, 21, qualified for semi-finals in the men's 100m butterfly and 50m freestyle respectively.
Proud and Guy will compete in the semi-finals in the early hours of Friday - the action starts from 02:03 BST.
Ledecky breaks Adlington's Olympic record
American Katie Ledecky set an Olympic record of eight minutes, 12.86 seconds in her women's 800m freestyle heat to beat the record set by Briton Rebecca Adlington at Beijing 2008.
Ledecky, 19, is the defending Olympic champion and is looking to add to her four medals already won in Brazil.
A silver medal in the 4x100m freestyle relay was followed up by gold medals in the women's 200m and 400m freestyle, as well as the 4x200m relay.
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