"He missed our 2008 World Cup win and his inclusion will be a great asset in trying to repeat that success this year. It's not only his footballing ability, but also what he brings off the field which will benefit the team.''
It was a tough call on the 21-year-old Harris, who made his Kiwis debut in this year's Anzac test.
"As you would expect, I'm very disappointed not to be heading to the World Cup to represent my country, New Zealand,' Harris said in a statement. "I was very much looking forward to going, however I understand the decision that has been made and hope I get another opportunity to play for the Kiwis in the future.''
"My focus will now be on returning to training with Storm in November for pre-season and looking forward to an exciting 2014.''
The Kiwis were keen to take Harris to the UK in a development role, which would have seen him travel with the squad and play pre-tournament against the Cook Islands, but the Storm have decided it's in Harris's best interests to stay in Melbourne and have a decent off-season. The 21-year-old, who made his NRL debut for the Storm in the World Club Challenge in the UK in February, will instead bring forward minor surgery.
"Tohu handled the situation as well as anyone could,'' Kearney said. "It was a conversation no coach would like to have, but he's a terrific young man and I'm sure he'll have many more opportunities to pull on the black jersey. It's been a unique set of circumstances for all involved, but for now our focus is getting set to defend the World Cup with the team we have.''
They will have a better chance with Williams, who played a huge role in the Roosters' premiership in his first year back in rugby league and is a player who will worry opposition sides.
He explained his stance earlier in the day with a statement on Twitter.
"After a few tough seasons topped with an amazing one with the boys at the Roosters, I was then faced with the opportunity to have a long-awaited break and go on holiday with my family,'' Williams said.
"Without thinking the whole situation through thoroughly, I eagerly jumped at the chance to chill out and rest. After having some time to really think about how much representing my country means to me, I decided to then put my name forward for selection.
"Now I know the squad's already picked and I understand if I can't be a part of it, but I'm here and ready to help the brothers if they want me.''
Williams' backflip could have something to do with the fact he wants to leave behind a legacy in sport. He has won a rugby union World Cup, two NRL titles, a Super Rugby title and a heavyweight boxing title and a rugby league World Cup would only enhance his standing. He's also played only seven tests for the Kiwis, with his last in 2008, and never been on the winning side in a black-and-white jersey.
