Israel Dagg faces an undetermined spell on the sidelines after a knee injury ruled the winger out of New Zealand's Rugby Championship clash with South Africa.

Dagg was omitted from Steve Hansen's selection for the match in Albany due to the long-standing problem that he aggravated during last week's win over Argentina.

The 29 year-old – who missed the opening two matches with Australia – was replaced in the 49th minute of that 39-22 win over the Pumas, and the All Blacks coach is unsure how long he will be without his winger.

"We are getting more information on that," Hansen said. "It doesn't look great at this stage.

"It looks like he might need some time away from the game but until I get more information it would be pointless to tell you how long or what is wrong."

Last weekend's win over Argentina came thanks to a second-half revival in New Plymouth, the All Blacks having been behind at the break.

That made it three victories in as many matches, but the world champions have been far from their fluent best, although it is not something that worries Hansen.

"When you're behind and 15 minutes into the second half and we managed to come back and win it, and comfortably, it's not all bad," he said. "Last week we scored six tries. Only one side has done that against Argentina - us. So it was a pretty good achievement.

"Yeah, it's a bit tough at the moment. But I believe we are going in the right direction. We have a good plan. If you're not happy with where we're going, be patient.

"It's another two and a half years before we get to the point where I would like us to be. We'll get there. I promise you."