All Blacks coach Graham Henry is worried about the depth of talent available at lock as he looks ahead to the international rugby season.
Henry has closely monitored the form of the New Zealand sides in the Super 14 ahead of the international schedule, which starts with a Test against Ireland in Wellington on June 7.
The All Blacks then host England for two tests before the Tri-Nations against South Africa and Australia.
New Zealand's locking stocks have thinned considerably since last year's World Cup, with Chris Jack and Greg Rawlinson now playing overseas and Keith Robinson having retired.
Ross Filipo has been sidelined due to a back injury and James Ryan has taken an indefinite break from the game as he continues recovering from serious shoulder and knee injuries.
It has all left Henry and his fellow selectors with much to ponder before the Irish team arrive in New Zealand, despite incumbent Ali Williams being an obvious stand-out to date with his form for the Crusaders.
Henry pointed out that the issue surrounding the locking position was not a new one.
"We've had problems at lock before. I remember in 2004 we really struggled to find enough locks to take away on the end-of-year tour," Henry told Radio Sport.
"I think the same thing is happening.
"It is an area of concern because there is not a lot of depth there."
Henry was not so concerned about his options at inside centre, despite both of last year's number twelves, Aaron Mauger and Luke McAlister, now playing their trade in Britain.
"I think there are a number of players who can play there," said Graham.
"I don't think the problem is as great as lock.
"There are a number of guys in the midfield who can play either twelve or thirteen so that shouldn't be as great a challenge as the lock forward challenge."