Ian Foster believes New Zealand are happy to stay patient with Sonny Bill Williams despite having a midfield quartet “jumping out of their skin”.

Cross-code international Williams racked up his 50th New Zealand cap as the All Blacks eased past Australia 37-20 in Yokohama on the last weekend of October.

The 33-year-old powerhouse centre should now line up against England at Twickenham on Saturday, with All Blacks bosses still confident in his ability to turn it on when it matters most.

“Sonny’s had the least rugby, he’s still finding his top form; I think that’s fair to say,” said New Zealand assistant coach Foster.

“I don’t think our patience (in Williams) will be driven by his background, more based on how we see players perform in training.

“I think when we look at the physical nature of the game, how they are training, sometimes things are going really good off the park and it hasn’t quite gelled to the extent they want on the park.

“Sometimes players are deemed to have had a quiet game but – in reality – they may not have had too many opportunities to show what they are good at.

“We’ve got a whole lot of players who have had injuries this year, significant injuries over time, and they’ve come back and at various degrees of accuracy in their game.

“But also some of them have taken a little longer to get their feet right.

“So as long as we’re seeing improvements in training, things are going good and the attitude’s good, I guess we just keep on making decisions we’ve been making.

“All our midfielders right now are actually jumping out of their skin, to be honest.

“In the last two weeks, the energy levels and work rate is as good as it’s been all year in that group.

“Then you put the performance of Ngani (Laumape) in Tokyo into that mix and that creates it’s own degree of pressure doesn’t it. So it’s a nice place to be.”

Matt Proctor made his All Blacks debut in last weekend’s 69-31 victory over Japan in Tokyo, where New Zealand fielded a side with more than one eye on the future.

The brunt of the All Blacks’ frontline stars were in London preparing for this weekend’s clash with Eddie Jones’ England, instead of Japan, leaving the back-to-back world champions in as rude health as ever.

Jack Goodhue is back in action following glandular fever, with Foster hoping the 23-year-old Crusaders centre will be at full-tilt for a physical England encounter.

“Jack’s keen, he’s certainly trained well, as have the other centres,” said Foster.

“There was a bit of fatigue with him at the end of last week, but he’s had a couple of days’ training and looks 100 per cent.

“Again, we’ll see, but hopefully we’ve got four midfielders ready and available.”

Asked if it has now become difficult to gauge the All Blacks’ best centre combination, Foster added: “We’ve got an idea, but we’ve been pleased with the performances of all four of them.

“Whenever they have gone out they have done a good job.

“We’re delighted the way the four of them are working together, discussing the game and growing the collective part of the midfield. That’s a real positive for us.”