The All Blacks suffered a fresh injury scare Tuesday with loosehead prop Tony Woodcock becoming the third member of the squad to be sidelined before the World Cup begins.

The 76-Test veteran Woodcock has a fresh hamstring strain and joins Adam Thomson (elbow) and Kieran Read (ankle) in the medical room.

Forwards coach Steve Hansen downplayed Woodcock's latest injury but could give no gaurantee he would be available for the tournament opening match against Tonga on Friday.

"We're hoping he'll be okay. He's got a bit of a twinge in his hamstring. They think it's just scar tissue from the previous hamstring he had a month ago," Hansen said.

Woodcock had been out of rugby for three months with ligament damage in his foot and only returned to the Test arena in August for the All Blacks last two Tests before the World Cup against South Africa and Australia.

The All Blacks have only the bare minimum three loose forwards fit to play Tonga - Richie McCaw, Jerome Kaino and Victor Vito - with lock Sam Whitelock who has played as a No.6 being groomed as a replacement if required.

The All Blacks medical staff remain hopeful Thomson will be available for their second World Cup match against Japan in Hamilton on September 16, but the outlook for Read is less clear.

However, Hansen denied it was a gamble keeping him in the squad and was hopeful the backrower would play in their final pool match against Canada on October 10.

"He's world class player and if he's going to be right by Canada or even the quarterfinals it's not much of a gamble."

Under World Cup rules, teams cannot bring in temporary replacements for injured players.

AFP