"He is still heavily involved with the planning but obviously right now the key thing is that he spends a lot time with his family as well,'' Foster said.
"We just carry on as normal. We've got good structures in this team and good people, so we're just trucking along and he's having some input into that.
"We're all feeling for him but the best thing we can do now is to let him spend time with his family and prepare well for what will be a very exciting test match.''
Centre Conrad Smith suggested the team could draw extra motivation from what Hansen, a popular figure with the players, was going through.
"If anything, you draw from it and we'll be supportive as we always are when one of us goes through something like this,'' he said.
Foster said the team had gathered in good shape following their week-long break after the rigours of winning the Rugby Championship which had ended in tough away matches against Argentina and South Africa.
"The reality is it's the third Bledisloe test and we've already won the Bledisloe Cup. You could say there is reason to not do well but for us we have a lot of pride in how we prepare and play and we want to put it all out there on Saturday.
Smith added: "We're in a pretty buoyant mood at the moment. We've been playing well and stringing some wins together and starting to play really well. We want to keep riding that wave and are aware that it takes a lot of hard work. We're about to play a Wallabies side that will want to ambush us, they'll be looking forward to that.''
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