When asked what he wanted to see from the injury-prone second-five against the Springboks on Saturday night, the All Blacks coach's answer was to the point.
"We want to see him stay on the park," he said.
"If he comes off it's because he's run out of energy as opposed to injury. We know he can play to a high level so it's his durability at the moment that's been affecting him getting on the park. We just want to see him put some minutes together then assess it from there."
Hansen was asked about his expectations of other players during his press conference on Thursday and spoke more about them needing to nail their individual roles in the team.
The talk about Williams' fitness was particularly pointed in that context.
Hansen knows Williams can nail his role if fit, but has to see him get through some games, especially while Ryan Crotty is out with a broken thumb, if he's going to put him on a plane to Japan for the Rugby World Cup.
His circumspection about the 33-year-old's durability is not without cause.
Since Williams' ruptured achilles tendon injury playing for the New Zealand Sevens team in August 2016, he has had two knee injuries, two shoulder injuries, two head injuries, one wrist injury and one hamstring injury, with the latter occurring at the All Blacks' pre-Rugby Championship camp two weeks ago.
While the focus for Williams was getting through the minutes prescribed to him this week from the coaches, others in the 23 have to impress with their form if they are to book themselves a ticket to Japan.
One of those is Shannon Frizell, who starts at blindside flanker, a position which appears to be genuinely up for grabs in the All Blacks starting XV.
Hansen said Frizell's focus should be on doing his job well, but that it wasn't just the Highlanders loose forward facing a Last Chance Saloon for his World Cup prospects.
"That's the same every time you play for the All Blacks. If you start to think you own the jersey you won't be there very long.
"You only pass through it, and every game you play you should be treating it as if it's your last, or your first, and respecting the jersey for what it is. Give a performance that warrants you wearing it again.
"I always chuckle when I hear people say 'Last Chance Saloon', it's the same every time they play, the pressure is on to play well."
It was put to Hansen that captain Kieran Read could be a candidate for the No 6 jersey, given Ardie Savea's formidable form at Read's preferred position of No 8.
Hansen didn't completely rule it out, but also didn't want to give too much away.
"You'll have to wait and see. There's no point me telling the world what we're doing. They can find out. It's a good question but I can't answer it."
So the hunt for the All Blacks starting No 6 goes on.
A resolution at that position looks unlikely until the World Cup rolls around.
Vaea Fifita and Dalton Papalii are on the bench on Saturday, while Luke Jacobson is out of the 23 after impressing in a cameo against Argentina.
Scott Barrett will have a scan on his broken finger on Monday and is an outside chance of playing in the Bledisloe Cup.
Highlanders loose forward Liam Squire ruled himself out of the Rugby Championship and Hansen said "not at this stage" to a question about if he would return for the Bledisloe Cup tests.