Know before you go - AdventureSmart

There's a major challenge from across the Tasman, including two former winners, for next month's 21st Port of Tauranga Half Ironman at Mt Maunganui.

Three-time winner Rebekah Keat and the 2008 champion Kate Bevilaqua will be joined by three other Australian-based stars that will provide a stern test to the kiwi contingent.

Olympian Samantha Warriner and Taupo's Duncan Milne will defend their titles in the country's most popular triathlon, which doubles as the official Triathlon New Zealand national championship on Saturday 9 January.

Keat and Bevilaqua will be joined from Ironman Western Australian winner Tim Berkel, talented Canberra athlete Alison Fitch along with Queensland-based Swiss star Caroline Steffan.

Internationals have had reasonable success at the Port of Tauranga Half Ironman with the women's winners including American Corey Lyons in 1991 before a string of Australians started to dominate. Robyn Roocke triumphed in 2000 before Keat won three in a row from 2002 to 2004 and Bevilaqua surprised to win in 2008. There's only one male from overseas to win with the victory of Australian Craig Alexander in 2005 the impetus for him to go on to triumph in the Ironman 70.3 (half ironman) World Championship and the Ironman World Championship in 2008 an 2009.

Berkel won the 2008 Ironman Western Australia title and has had a raft of top-five finishes in 70.3 races in Australia, Asia and USA including two wins and five podiums this year.

"I have been wanting to race in New Zealand for several years, but I haven't had the opportunity because of my schedule. I have been racing against Kiwis for a few years now, so in conversation, I'm always aware of the bigger races that are happening in New Zealand, it's just unfortunate that I haven't been able to race there until now.

"I'm really excited about it. Not only have I not raced in New Zealand before, it will be my first time in New Zealand period."

It's been a frustrating time for Bevilaqua since her outstanding 2008 victory when she came from behind to beat Jo Lawn and Keat. After finishing runner-up in Ironman New Zealand, the Western Australian suffered a series of mishaps, breaking her shoulder after being knocked off her bike, suffering a stress fracture and then had a recurrence of the injury after returning to training too soon.

After more than a year out of the sport, she returned to finish fifth at Ironman Western Australia this month.

"I had my fair share of up and down moments but with fantastic family, friends, sponsors and just an awesome support network it didn't take long to pick myself up again," Bevilaqua said.

"In the big scheme of things this was just a minor setback. But when you love racing so much, it can be hard to take."

"Of course I would love to win again. Winning Tauranga in 2008 was my first professional victory so that race will always be special to me. Plus the crowd and community support, it is a great place. I can't wait to return and race again."

Keat is always a popular competitor at Mt Maunganui where she achieved her breakthrough victories. She came back after a disputed drugs ban to finish second in Ironman Australia in 2007 and 2009. Keat finished fifth at the Ironman World Championships in Hawaii in October only to be disqualified for receiving three penalties on course.

Fitch has a series of top-five finishes over the Half Ironman distance and Ironman in Australia and North America over the last three years. She is an excellent swimmer and rider and is expected to be in the mix.

They all may have to watch for 31-year-old Swiss triathlete Steffen. Currently based in Australia, Steffan was narrowly edged out of the podium at the recent Ironman 70.3 World Championship in Florida. She was third in her age group at the Ironman World Championships three years ago, third in last year's Ironman Australia and recently won the Gold Coast Half Ironman, the sister race to the Port of Tauranga Half.

The rest of the elite field and seedings will be finalised later this week.