Krupicka had always wanted to travel to New Zealand so a personal invitation from race director Paul Charteris and an offer from Kawerau-based engineering firm Allied Industrial Engineering (AIE) clinched the deal.
AIE manager Stephen Hayes said having Krupicka in Kawerau meant tens of thousands of running enthusiasts worldwide would focus their attention on the town for the day.
The Tarawera event includes 60km, 85km and 100km races, with competitors running mainly off road from Rotorua to Kawerau. Krupicka heads a 100km field that is by far the strongest in the race's four-year history.
"This will be the most competitive 100km running race in New Zealand's history. I also reckon it's also one of the best distance running fields this country has ever seen," Charteris said.
"There's never been a race like this in New Zealand before."
Pushing Krupicka will be Australia's two best ultramarathon runners, Mick Donges and David Eadie, the 100km Australian champion and his country's ultra runner of the year.
The best of the UK will be here, in the form of Stu Mills and UK fell-running champion Martin Cox.
And Japan's highest profile ultra runner, Hiroki Ishikawa, will also compete.
The international challengers will be joined by a strong Kiwi contingent.
Christchurch's Vajin Armstrong finished second in last year's race and has won the last two editions of the Kepler Challenge, a 60km mountain run in Te Anau. Fellow Cantabrian Martin Lukes is the national 100km titleholder while Kristian Day (4th last year) and Dave Heatley, winner of the 2011 Tarawera 85km, also join the field.
The women's line-up is also strong, headed by Canadian Nicola Gildersleeve.
Charteris is understandably thrilled by the talent the race, which was included in the 2011 book World's Ultimate Running Races, has attracted this year.
He said he hoped the calibre of entrants would focus national and international attention on the event and the area.
"Without any doubt this is a true world-class field and a major coup for Rotorua, for New Zealand and indeed for Australasian ultrarunning," he said.
Entries are still open for the event, which has attracted over 240 entries from 12 countries. For more information visit http://www.taraweraultra.co.nz/.