Angus Bates, 21, and Geoff Watson, 53, have never swum competitively before in the ocean and both have mixed emotions about what they will face.
Watson suffers from cerebral palsy and for more than 20 years has swum with just one arm and one leg. He says he is looking forward to Saturday's surf swim even if he is not absolutely sure how it will go.
"It is going to be another challenge, especially with my cerebral palsy. Finishing is what I am most looking forward to.
"I am not thinking of it as a race as I know other people with two arms will do better than me. It is a personal challenge."
Younger swimmer Bates is a renowned pool specialist who wiped eight seconds off his personal best in the 200m freestyle at the Special Olympics nationals in Dunedin last December.
But the surf swim is new territory for him.
"The only time I have swum in the ocean is to get to my kayak when I fall out," he said. "It will be a bit different, something I have never done before. I will try and beat Ben. There is a lot of competition between us."
That Ben is Ben Motion, 31, who won two gold and two silver medals at last year's Special Olympics nationals.
He finished last year's surf swim in 5m 25s and wants to go quicker on Saturday.
"To get there in under five minutes is the goal.
"It is definitely harder swimming in the ocean because you are swimming against the current and the tide.
"It is cold plus you have the wave pushing against you. It was tiring but it was a real buzz. I like a challenge." he said.