The pair started the press conference at Waitakere Trusts Stadium in west Auckland by answering questions on behalf of the other, including a response to a query from TV3 rugby reporter Jim Kayes to Sonny Bill about his yellow card for a shoulder charge in the semifinal.
"We don't have much to say on that,'' Ali replied, adding: "That frustrates you doesn't it Jim? Look at you.''
Kayes replied: "We're just trying to say professional and sort of expect the same from you guys.''
"So let's talk about the game then, why about one incident?'' Ali asked.
Kayes: "Because Sonny's up here and we'd like to ask him about it.''
Ali: "It was just a tackle gone wrong.''
The two Williams found it funny, and Stephen Donald, who was sitting beside them, laughed nervously, but the assembled media who were gathered to ask questions of the All Blacks ahead of the biggest game of their careers, did not.
It is understood that Kayes will take the matter further with All Blacks management.
Normal transmission resumed after the standoff but it was a disappointing performance from the two Williams - and Ali in particular.
No doubt he will respond by saying the All Blacks are getting tired of the same questions week after week and wanted to spice things up a bit, but it wasn't appropriate behaviour from a senior player in such a big week.
Fifteen minutes of answering questions about the game and surrounding issues surely isn't too much to ask. Say what you like about the Wallabies but they would never stoop to such antics in front of the media.
Ali Williams went on to say he he had been amazed at the New Zealand public's support of the team throughout the tournament and that had reached a new high in Sunday's semifinal victory over Australia.
"I've never seen the country like this in my life. I was here in '95 when we won the America's Cup and that was pretty phenomenal but this is just another world. I haven't had to pay for one breakfast at my local cafe yet which is brilliant, but also the flags on the cars, the excitement of people getting into it.
"They probably haven't focused too much on the result, they've focused on the whole event and for Kiwis that's pretty special and I think we can walk away from this and learn regardless of what happens in the weekend.
"That atmosphere in the weekend was one of the best I've ever been in. I think the reality is when people are roaring like that you don't miss a tackle. You've got that extra half a centimetre in your stride. It's just mind blowing the noise that's generated and the reality is it does things for you when you're playing that you can't explain.
"It's the excitement levels that get to us and the reality that we don't want to let anyone down. Sometimes you need a kick in the back or raw excitment to get you going and that's what it's doing.''
That wasn't that hard after all, was it Ali?