Jane has a minor hamstring strain that will take at least two weeks to heal, but the medics fear he'd be highly likely to damage it again if he were to be available to play against Wales.
The decision was made on Sunday morning US time to send Jane to New Zealand rather than take him to London.
Harris, who had initially looked like he would be okay despite hobbling off early in the test, has done more damage than first realised. He has torn medial ligaments in his ankle and is looking at a six-week lay-off.
"Cory Jane has pulled his hamstring and Doc thinks that is probably a two-week injury and with a high risk that if he plays in the Welsh week, it will pull again so he's going home," All Black coach Steve Hansen confirmed.
"We won't be naming a replacement for him until we get to London.
If we look after him right then it will settle down and it will be fine. We know he's a world class player and he's shown us that through the season at times.
"It is just a matter of him coming back and playing a good Super season and he will be a pretty hard man to leave out of the squad.
"Nathan Harris has also woken up sore and it looks like he may have torn the medial off his ankle which is a six week injury as well so he's going home.
"It is unfortunate for Nathan. He has worked really hard and was in a good place and we are going to miss out on giving him some time.. We know through what he has been doing at training that he is on the right track."
Hansen said the decision about replacements wouldn't be made until the team arrived in London because he and assistant coach Ian Foster had to talk to New Zealand-based selector Grant Fox first.
They also needed to assess the various candidates – particularly at hooker as some have struggled with injury and others haven't played much.
One man not in contention is Motu Matu'u, who has a damaged shoulder.
- Gregor Paul of the Herald on Sunday in Chicago
