Cool water temperatures and strong tides are expected to favour New Zealand swimmers in the final Olympic qualifier for the 10km open water swim in Portugal at the weekend.
The four-strong New Zealand contingent are fighting to fill a spot among the remaining nine places open in the men's and women's competition for London.
Swimming New Zealand open water manager Philip Rush took the quartet of Cara Baker, Charlotte Webby, Jonathan Pullon and Kane Radford to Europe three days ago.
"We wanted to ensure they were able to settle after the travel and be well prepared. The hotel has filled up now and there's a real buzz of expectation," Rush said.
The current water temperature in Setubal Bay, just south of Lisbon, is 16 degrees Celcius.
"It's cold for sure and that will suit our swimmers. They have come out of cold conditions at home and are used to swimming in this," Rush said.
"It is also quite tidal and the current will definitely play a part. Navigation and tactics will be a factor as swimmers go against the tide up the course and back with it."
Rush is predicting stern competition for the New Zealanders with 62 men and 40 women entered.
There are nine spots remaining for men and women to complete the fields for London, with only one swimmer per nation eligible to qualify.
The men's field includes high-quality swimmers like David Davies (Great Britain), who was second in the 10km at 2008 Olympics, and Ossama Mellouli (Tunisia) who won the 1500m freestyle at Beijing.
The women's line-up is also going to be very competitive because the USA have not qualified, so their two best open water swimmers are competing.
"It's going to be very tough but I think we are in good shape."
Rush is hoping for a strong pace over the six laps of just over 1.6km to ensure the race does not come down to a bunch sprint.
"It is certainly our best chance. There's so much riding on this I expect the strongest swimmers will want to set a good pace."
The team have one further light training swim tomorrow before resting up for the weekend with the women's 10km race from 4pm local time on Saturday and the men's race on Sunday.