Highlanders loose forward Adam Thomson and Chiefs player Liam Messam, who was called in on Sunday as cover, are also options.
The reserves bench will already have a different look with the likely inclusion of Blues hooker Keven Mealamu, finally available after his niggling calf injury, and Crusaders lock Luke Romano, who will come in for the injured Ali Williams.
Halfback Piri Weepu, who has been forced to bide his time behind newcomer Aaron Smith in the two contrasting victories over Ireland, said Read would be a big loss but backed McCaw to excel in the unfamiliar role.
"Reado is a huge, key player obviously between the backs and forwards, so that position demands quite a bit and we've got to make sure we work really hard with whoever takes on the No8 jersey, if Reado's not fit," he said, adding of McCaw: "If he's named there this week we'll definitely do a lot of work around calls and what we want out of the scrum and what we want him to do when things don't go the way we want.
"He's played there a number of times and I guess it's just a matter of making him feel comfortable in that position and taking the stress off him as much as possible at the back of the scrum."
There is likely to be a fair bit of talk from head coach Steve Hansen to ensure he has a less stressful end to the week.
After the freezing encounter in Ireland he was hot on the silly penalties given away through ill-discipline and privately he would have been aghast at how his side came off second best in the contact areas. A retreating second-half scrum will also be a concern.
"Obviously we didn't have it quite right last weekend and although we have won the series it's never-ending for us," Weepu, who iced a tight hamstring after training, added.
"We've always got to improve and we definitely want to improve from last week's effort. Everyone this week is out there trying to make sure we get the little things right."
One of the All Blacks' strengths is how they work for each other, and that applied in the case of Weepu, who has played 58 tests, and new rival Smith.
"We always sit down and have a coffee together and chat over what we need to do as halfbacks during the week to prepare ourselves for the game," Weepu said.