In an impressive performance, Kyle Lee has secured 13th place in the men's 10km marathon swim, perhaps one of the most gruelling events at the Paris Olympics.

Hailing from Bunbury, in the WA's South West, Mr Lee's Olympic debut showcased his signature strategy of a strong finish as he clawed his way back from 20th place.

Though neither he nor fellow Australian Nick Sloman, from the Sunshine Coast, were able to secure a podium finish, both men displayed incredible athleticism. 

Lee, 22, battled his way through heavy currents and low, bright sunlight before he crossed the finish line at 1:56:42.5, just 18 seconds behind Sloman.

The race took place in the famous Seine River, recently the focus of widely reported pollution concerns. 

Prior to the race, Lee said he was not fazed by the reports and placed his faith in the officials to determine if it was safe. 

"It honestly felt like swimming in any other stream or lake; it felt like normal water really," he said after the event.

Lee's family moved to Bunbury from Zimbabwe when he was six to give him and his sister a better chance at a future.

"I've been very fortunate my family made the move to Australia. It's given me so many opportunities, and to be able to represent my country and have the Australian flag around me is so special."

The support from his family has played a vital role in what he has achieved, with some of his earliest memories of playing in the pool with his sister.

Lee has said it was his dream to compete at the Olympics but, according to some of his friends, he was a late developer.

Alex Saffy, who will be competing at the Paralympics kicking off on August 28, is a training partner and friend of Lee's. 

He said it was only in the last five years or so that Lee filled out and his body caught up with his work ethic. Since then, Lee has gone on to win the Busselton Jetty Swim five consecutive times.

Saffy said it was amazing seeing his friend compete at the Olympics, but was not surprised with Lee's strong finish.

The Paralympian said he believed Lee had the strongest finish of any long-distance swimmer in Australia.

"It's crazy. It really motivates me because 13th place is pretty amazing. So, hopefully, I can do similar," he said.