Great Britain’s contenders for the Rio Olympics will aim to prove their credentials at the World Triathlon Series in Abu Dhabi on Saturday.
Alistair and Jonny Brownlee have already qualified for Rio and will not compete until later in the season.
Vicky Holland and Non Stanford have also met the qualification criteria.
A place on the men’s and women’s team remains, with rivals Gordon Benson and Tom Bishop, and Jodie Stimpson and Helen Jenkins, battling it out.
Bishop, a world under-23 bronze medallist in 2012, Commonwealth champion Stimpson and two-time world champion Jenkins are on the start list for Abu Dhabi.
Bishop will also be joined by former British champion Adam Bowden, 34.
But European Games champion Benson has opted to train in Tenerife with Alistair Brownlee and will start his season on the Gold Coast in Australia on 9 April.
Selectors for the men’s team are looking for a support partner for the Brownlees with qualification for the British team to be decided by the Yokohama race on 14 May – the fourth World Series race of the year.
But a decision on the women’s team will be based on their medal potential and made after the Gold Coast event.