Rotorua teenager River Mutton has picked up New Zealand's first individual medal at a junior canoe slalom world championship, snaring bronze in the extreme slalom final in Italy overnight.

The 16-year-old overcame disappointment in her under-18 K1 semifinal earlier in the day to bounce back, finishing second in her extreme quarter and semifinals and then holding on for third in the four-boat final, behind Czech paddler Katerina Bekova and French paddle Alix Degremont.

'I was super-happy with third - it was a pretty tough final and we all got a bit tangled up off the start,” says Mutton.

'I got spun out of the down-gate on the drop and missed it and ended up being in the eddy for a while trying to find a way back down it.

'I ended up miles behind the others but one girl had some trouble with the same down-gate too and couldn't get round it.”

It's the first New Zealand medal at the joint under-18 and under-23 championships since twin success in Penrith in 2014; Daniel Munro and Luke Robinson won silver in the under-18 men's C2, while Jane Nicholas, Haylee Dangen and Kelly Travers won bronze in the under-23 women's C1 teams race.

Earlier, Mutton finished 25th in her K1 semifinal after missing Gate 8 and picking up a 50sec penalty.

Slovenia's Eva Hocevar clocked 89.67sec to win gold in the final, well ahead of Slovakia's Sona Stanovska's 93.23.

Tauranga's Courtney Williams also finished 25th in the under-23 women's K1 semifinal, with a time of 124.05secs.

Frenchwoman Camille Prigent broke through for the biggest win of her career in the final, with the two-time junior world championship bronze medallist clocking 89.31secs, well under the 92.64 set by Austria's Lisa Leitner.

The final day of the championship starts this evening (NZ time) with Hannah Thomas racing the under-18 C1 semifinals, Zack Mutton in the under-18 K1 semifinals and Callum Gilbert, Jack Dangen and Finn Butcher all qualified for the under-23 men's K1 semifinals.