New Zealand fly-half Dan Carter and prop Tony Woodcock have been ruled out of Sunday's Test with Ireland.
Both men picked up injuries in Saturday's 30-22 victory over England at Twickenham.
Carter's 100th Test appearance was cut short when he limped off with an Achilles injury in the first half and Woodcock did not emerge for the second period after hurting his hamstring just before the break.
Both men will fly home whilst the rest of the squad goes to Ireland where they will attempt to become the first international team in rugby's professional era to win every match of the season.
"Dan has not had a scan yet, but (team medics) said with the problems he's been having it's just too big a risk to go through the week," Hansen confirmed on the All Blacks official website.
"We've got Crudes (Aaron Cruden) and Beauden (Barrett) who can both do the job, so we'll just get on with it with those two."
Carter was already scheduled to take an extended break from the game after the Ireland Test to try to ensure he is fit for the 2015 World Cup.
Carter, 31, will sit out England's three-Test tour to New Zealand in June next year and most of the 2014 Super Rugby season.