Record times are expected to be threatened by a strong field at this year's Kawerau King of the Mountain event.

The annual race, being held for the 64th time this Saturday, is only about 8km long but sees runners climb 852m above sea level.

The race is capped at 200 starters and late entries will be taken on the day. Around 150 pre-entries are in, with the record number of starters being 177 in 2015.

With more last-minute entries possible, it looks like the 2017 race will be one to keep an eye on.

In the men's field Australians Mark Bourne and Ben Duffus are likely contenders for the king title. The current Kiwi contenders are Chris Morrissey, with eight titles, and Sjors Corporaal, with four. Both have sub-50 minute times in them and that is what it will take to be crowned king. Aside from vying for the ultimate crown, they will fight personal battles to be the fastest Kiwi veterans.

There are also exciting prospects in the juniors. Kaya Corporaal and Regan Wilson are the most likely contenders to take out the junior ranks or push for the overall title.

In 2011, current record holder Shay Williamson won his first crown at 18-years-old - his record stands at 45:31. It is going to take a superhuman effort for someone to break it but, with Williamson not likely to defend his title, the record is up for grabs.

The race will come down to a sub-50 minute finish time. An astonishing 29 competitors have indicated they are aiming for sub-60 times and seven of these are hoping for sub-50 times. In 2016, 24 entrants achieved a sub-60 time. Of these, four went below 50 minutes and the record was broken.

Kawerau District Council events and venues manager Lee Barton, who has been involved with the race since 2009, said anyone could show up on the day, making it hard to predict the outcome.

"There is no doubt the calibre of athlete has improved beyond belief and the times keep pushing the limits. Barry Prosser was the last veteran to be a king, so you never know," Barton said.

There is no clear favourite in the queen race. Last year's winner Ruby Muir is not likely to defend her title, leaving the field wide open. Australian-based Swede Ashild Krige is the Australian queen hopeful, though she is relatively inexperienced with the size and scale of Putauaki.

Rotorua-based Emmelie Gulliver will debut in Kawerau and could pull out a surprise. Kawerau local and last year's number one junior Jana Longney may be a genuine contender in what is a relatively inexperienced female line-up.

Weather will influence whoever takes part in the race and entrants will be hoping for cool overcast conditions similar to 2016's race. With this in mind, competitors should take special care of pre-race water hydration. New Zealand is enjoying a warm, sunny spell and race organisers would like athletes to focus on maintaining hydration.

"All those who are in the race are heroes, whatever their ability. Putauaki is an incredible challenge and we hope the crowds come out to support those in the race this year," Barton said.

Online entries close at midnight tomorrow. Visit www.kaweraukingofthemountain.co.nz for further information.

Race day schedule
Radio 1XX school relays - 9am
Prince & Princess of the Mountain - 11am
Kawerau King of the Mountain - 12pm
Prizegiving - 3.30pm