Meanwhile, top Kiwi athlete Bevan Docherty will defend his men's crown from last year.
Docherty and Kessler will join a record final entry of 1750 participants from 58 nations, the highest number in the history of the world's oldest international ironman event. The professionals will chase an increased prize purse of approximately $90,000 (US$75,000) along with qualifying points for the Ironman World Championship.
Docherty, the double Olympic medallist in 2004 and 2008, will return to his home town of Taupo where he won on debut last year, setting a new course record in the process.
It was a dream start to his ironman career following on from his third placing in the Ironman 70.3 World Championships in 2012.