The All Blacks and Sonny Bill Williams are reunited at last but uncertainty surrounds what sort of reception the game-breaking inside centre will get in Sydney during Saturday's Bledisloe Cup test.

Williams joined the squad in Auckland on Sunday night after clearance arrived several days later than expected from his Japanese club, Panasonic.

He was declared fit to play the first two Rugby Championship Tests against Australia this month.

Williams trained fully on Monday and assistant coach Ian Foster gave every indication his name would feature when the team is unveiled on Thursday due to the absence of injured outside centre Conrad Smith.

Williams was exceptional in the three Tests against Ireland in June, followed by the Chiefs' charge to the Super Rugby title.

"We're pretty excited he's here. He brings three games' experience in June, which enables us to have a bit of continuity," Foster told journalists.

"And he brings a lot of confidence himself given the way he's played in 2012."

Foster said there was ample time to get Williams up to speed for his 18th Test and his first on Australian soil.

Interest surrounds how Williams will be received in Sydney, given his controversial mid-contract walkout on the Bulldogs NRL club four years ago. He has since played rugby union in France and New Zealand for two years each.

"It (Williams' availability) is good for us, that's all we're focusing on," Foster said.

"Wherever he goes, there's usually a bit of news going with it."

The All Blacks were buoyed at training on Monday by the return of their rested Chiefs contingent, along with three non-squad members to boost numbers - Hurricanes first five-eighth Beauden Barrett, Chiefs halfback Tawera Kerr-Barlow and Chiefs lock Craig Clarke.

Everyone in the squad was fit for selection, including world class No.8 Kieran Read, who had overcome rib difficulties.

Foster admitted left wing was one of the hardest selection choices, with Julian Savea, Hosea Gear and Ben Smith all strong contenders.

Another challenge was filtering the game plan to the players at a speed which was easy to digest.

"It's exactly the same challenge as we had in June. We can't try to go in too complex and we can't over-train or put too much information in.