Beauden Barrett remains in doubt to line up for the All Blacks on Saturday, as concussion symptoms continue to linger.
Barrett copped a head knock in New Zealand's thrilling win against the Springboks a fortnight ago and did not take part in the final 30 minutes of that match.
He passed a HIA on the night but has been suffering headaches and dizziness ever since.
That has All Blacks officials taking particular caution with their star playmaker and he only took part in very light duties at training on Tuesday morning.
"He had a couple of symptoms through training over the last few days so he is just following normal protocols, really," All Blacks assistant coach Ian Foster said.
"We will progress him based on what happens the day before.
"He had symptoms two days ago after training so he will have a session in the gym today but overall, how he responds to that session will determine what happens tomorrow."
Foster said Barrett would not start unless he is 100 percent fit and ready to fire.
"There's still scope but we're not going to - we've said before if there is any doubt, he won't be playing," he said.
"It's Tuesday, we will do the best we can, see where he's at and let you know on Thursday."
Should Barrett be ruled out the All Blacks have two options.
Shift Damian McKenzie to flyhalf from fullback, or hand Lima Sopoaga a start, with Richie Mo'unga likely to come onto the bench.
McKenzie has been filling in for Barrett at training throughout The Rugby Championship and flyhalf is the position the coaching staff want him playing at the Chiefs, as well.
"Damian has been going in there regularly over the last four or five weeks at training," Foster said.
"Not to a great extent but enough and obviously Richie (Mo'unga) has come in for him to have a look at it.
"He's having a look at it today, we will have a yak tomorrow and see where he is at with the content but he will fit in well."
Barrett's younger brother, Scott, said it was frustrating to see his brother struggle with the knock.
"Our oldest brother, Kane, he's had to retire from (a head knock) so it's tough to see Beauden get that knock," he said.
"Fingers crossed he recovers shortly.
"He's doing the right steps and the doc is looking after him pretty well.
"I'm not sure what the coaches have said to him but I guess there is no rush to come back in until he's right."
Australia hosts New Zealand in the third Bledisloe Test on Saturday October 21, kicking off at 7pm local, 8pm AEDT, LIVE on FOX SPORTS, Network Ten, Win and via RUGBY.com.au RADIO. Buy tickets here.
