McCaw, 30, has been affected by a troublesome right foot and the attention on the talismanic forward's fitness intensified with the appearance of Crusaders flanker Matt Todd at training on Wednesday.
Todd, who also trained with the All Blacks ahead of their pool game against France, joined a number of the Blues' Super Rugby squad in an opposed session, with International Rugby Board regulations stating players not in the official 30-man World Cup squads cannot train with the team, only against them.
However, speaking at a press conference on Thursday, Hansen was keen to clarify the situation involving McCaw and Todd, saying: "I can guess what the first question is, so I'm going to answer it. Richie McCaw's foot is fine. Matt Todd is training with us, as you all know and have written about.
"Matt Todd is part of our wider training group and trained with us in Christchurch, as did other players down there. We've had wider-training group players come in for training at all the venues.
"Matt Todd is in Auckland and it just made common sense to have him here. Now that doesn't mean to say that Richie's foot is worse than it was. It doesn't mean that Richie is not playing on Sunday.
"It just means that Matt Todd was in Auckland and that we wanted to use him for training, as opposition. So hopefully that puts that away."
Aside from McCaw, reserve flanker Adam Thomson has also been struggling with an ankle injury but even if both players are ultimately ruled out for the showdown with arch rivals Australia at Eden Park, Hansen believes they have the strength in depth to cope.
"We're very happy where we are with our loose forwards," he said.
"Our loose forwards have got niggles but I'd suggest the other three sides, they'd all have niggles. That's what tournament rugby is about, the fittest stay the strongest and longest.
"Richie's obviously reasonably sore in the foot but he's still able to play. Adam's got an ankle, he's training, he just hasn't got over the hump yet.
"We don't need to replace them. We've got enough cover."
Meanwhile, Hansen also played down suggestions that Todd had been employed to mimic the playing style of Australia flanker David Pocock in training, adding: "No. He's being Matt Todd. Don't read too much into it - he's just at training. The poor guy is just at training and that's it.
"We've got plenty of people we can turn into David Pocock - just put a green bib on them and say 'you're David Pocock'."
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