Joseph Parker believes he is punching harder than any time in the last two years thanks to surgery on his elbows.
The Parker camp has confirmed the unbeaten Kiwi heavyweight underwent an operation in November to alleviate a restriction in his elbow movement which was causing pain.
The secret operation was revealed by The New Zealand Herald last night.
Read more: Joseph Parker had secret surgery
The Parker camp believes the 26-year-old will show the benefits in next week's unification fight against Briton Anthony Joshua in Cardiff.