Assistant coach Jason Ryan has revealed that the All Blacks captain will miss his original deadline for a return to Super Rugby, which was originally set at four weeks.
"[Read] is two or three, probably, weeks away. We are not 100 per cent sure yet," Ryan said.
"We will just see how he goes. He is back into his training, and so forth. We are pretty confident."
That could see him sidelined until the Crusaders' clash with the Hurricanes in Wellington on March 29.