Oita - All Blacks loose forward Ardie Savea will wear special rugby goggles when he plays against Canada in the Rugby World Cup as he battles vision problems in his left eye.

Savea will become the first player at a Rugby World Cup to wear the goggles, which were approved by World Rugby earlier this year to allow people who are visually impaired to play the game.

Savea, a bruising back-rower, and a key player for the defending champions, said the vision in his left eye was deteriorating and he needed to protect his eyesight.

"A couple of years ago I realised I had bad vision in my left eye. Everything's kind of blurry. I told All Blacks doctor Tony Page that it was getting worse and now we're doing something about it," he said, ahead of Wednesday's game in Oita.

"Doc notified me that World Rugby had some goggles that were approved and everyone has been really supportive. In terms of vision and seeing, it's pretty sweet, and it's now just a matter of getting used to them."

The goggles are designed to be safe for both the player wearing them and those coming into contact with the player.

Savea follows in the footsteps of Ireland-born Italian flyhalf Ian McKinley who was the first international player to wear the goggles, but has not played at a World Cup.

Page said Savea had worn the goggles at training and they hadn't affected his ability to play.

"It's probably been the most challenging conditions that you can get (to test them). Humidity at up to 90 percent, 20 degrees Celsius or so, and hard All Blacks training, and he's done pretty well. It's great to see someone like Ardie putting them on and being proud of it," Page said.

Savea said when he realised that he could potentially lose his sight if his other eye was damaged, then it had been an easy decision to make.

"I've got my little girl and hopefully future kids and a bigger family, so I want to be able to see," he said.

"I'm just thinking of the bigger picture and trying to protect my eyes."

Teams:

New Zealand

15 Beauden Barrett, 14 Jordie Barrett, 13 Jack Goodhue, 12 Sonny Bill Williams, 11 Rieko Ioane, 10  Richie Mo'unga, 9 TJ Perenara, 8 Kieran Read (captain), 7 Matt Todd, 6 Shannon Frizell, 5 Scott Barrett, 4 Patrick Tuipulotu, 3 Angus Ta'avao, 2 Liam Coltman, 1 Atu Moli

Substitutes: 16 Codie Taylor, 17 Ofa Tu'ungafasi, 18 Nepo Laulala, 19 Sam Whitelock, 20 Ardie Savea, 21 Brad Weber, 22 Ryan Crotty, 23 Ben Smith

Canada

15 Patrick Parfrey, 14 Jeff Hassler, 13 Conor Trainor, 12 Ciaran Hearn, 11 DTH van der Merwe, 10 Peter Nelson, 9 Gordon McRorie, 8 Tyler Ardron (captain), 7 Matt Heaton, 6 Lucas Rumball, 5 Conor Keys, 4 Evan Olmstead, 3 Cole Keith, 2 Eric Howard, 1 Djustice Sears-Duru

Substitutes: 16 Andrew Quattrin, 17 Hubert Buydens, 18 Jake Ilnicki, 19 Michael Sheppard, 20 Josh Larsen, 21 Phil Mack, 22 Taylor Paris, 23 Andrew Coe