The 25-year-old put himself in the medal mix by qualifying for the final in second spot but a mid-race error saw him lose valuable time and he faded to finish ninth.

His final time of 108.18 seconds included a two-second time penalty.

Watkins's time from his semi-final - 101.28 - would have been enough for a silver medal if it was in the deciding race.

Competing in his third Olympics, world No.7 Slovenian veteran Ben Savsek was flawless through the Tokyo course, crossing the line in in 98.25 seconds.

Savsek's win brought an end to the dominance of Slovakia and France in the event. They had won every gold medal since the 1996 Atlanta Games.

"I was trying before, but now I'm really happy to put on a really good run in the final. I'm living my dream," Savsek said.

"Every time I was aiming high, but never did well in the finals.

"We have been waiting for this medal a long time and it is the first gold medal for canoe slalom. I am really happy and proud."

Czech Lukas Rohan won the silver medal, 3.71 seconds off the pace, while Germany's Sideris Tasiadis was third.

Gold medal favourite Slovak Matej Benus finished sixth.

Watkins, who only switched from the two-bladed kayak paddle to canoe competition a few years ago, was on pace until the 15th gate when he came unstuck.

"One mistake but one really big mistake, which was a little bit annoying," Watkins told the Seven Network.

"I was pretty good through the top but after I got back from that mistake my arms were burning - I wasted 10 seconds basically paddling away from the finish line.

"I still got it together and had a good finish so I've got to be happy with that."

Australian teammate Jessica Fox will start as the red-hot favourite to win her first gold Olympic medal on Tuesday, lining up in the deciding races of the K1 event.

Australian Associated Press