Two-time open water world champion Keri-Anne Payne finished second at the final Olympic Qualification event in Portugal to secure a place at Rio 2016.
Payne, who won silver at the 2008 Beijing Games, required a top-nine result in Portugal.
China’s Xin Xin took victory, finishing the 10km race in one hour 55.12 seconds, with Payne 0.8 seconds behind.
Danielle Huskisson was ninth but the Scot misses out with only one athlete qualifying from each nation.
The men’s event will take place over the same course in Setubal on Sunday at 15:30 BST.
British Swimming already has Jack Burnell as a consideration for nomination to Team GB after he finished fifth in the 10km event at last year’s World Championships.
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