Ashleigh Gentle won a record seventh title while Jake Birtwhistle added a second Noosa Triathlon crown on Sunday.

Gentle has one more race on her 2019 calendar before joining Birtwhistle in an off-season that will revolve around preparations for July's Olympic Games.

Their victories rammed home the pair's class ahead of the discretionary selection process that will result in three men and three women making the cut for Tokyo.

Results on the world tour indicate both are realistic chances in their individual races, but the introduction of the mixed relay for the first time in Olympic competition is arguably Australia's best chance to return to the podium after missing a medal in Rio.

"It's going to be a massive year; the team isn't picked so we just have to put best foot forward and (if selected) we want to win medals, so we will band together and try and get one (in the relay)," Gentle said.

Australia has placed in the top three at the last five mixed relay world championships and will arrive with good options regardless of who makes the final team of six.

"Australia should have a really good team going into Tokyo in the relay," Birtwhistle said.

"Every world champs in the last three or four years we've been on the podium, so we should definitely be in contention.

"Ever since it's been included in the Olympics it's increased in importance for us."

Gentle, who eclipsed Craig Walton's record of six titles on Sunday thanks to another barnstorming run leg, was pleased to find form in Noosa after a year she admitted earlier this week she "hated" at times.

Birtwhistle took confidence from the win too, given he was able to run away from South Africa's Commonwealth Games champion and Rio bronze medallist Henri Schoeman.

The Tasmanian said he would be prepared for anything in Japan, where extreme heat will be likely on race day.

"I think an absolute stinker of a day is guaranteed in Tokyo," he said.

"I don't have to wish for that too hard, just have to make sure we're there prepared for the heat and humidity."

Australian Associated Press