All Black Kirk turns Wallaby

Wellington - The All Blacks and New Zealand suffered a shock loss on Monday when the only All Blacks skipper to hoist the rugby World Cup switched teams and became an Australian.

David Kirk, who led the All Blacks to victory in the inaugural 1987 World Cup final, became Australia's newest citizen in a ceremony aptly held on Australia Day.

"We've lived here as a family for 10 years. My children have grown up here, particularly the younger one, and it just seemed like the right time," he told Television Three News.

But Kirk said his heart still belonged to New Zealand and he would hold dual citizenship.

"I grew up in New Zealand. My heart, my emotion, my commitment of course is to New Zealand."

Kirk also confirmed he would always back the All Blacks over the Wallabies.

"Of course I'm an All Blacks supporter. I'm a massive All Blacks supporter and it's the All Blacks all the way."