"The dream wasn't over when Steve rang me and said a couple more weeks, but next week it will definitely hit me ... but in saying that, who knows what the future holds?"
The emotions will be put on hold this week, he said, just as they were during the week of the Chiefs' final against the Sharks. He wants to end his stint at the All Blacks with a more polished performance than the one he put in alongside Ma'a Nonu in Sydney last weekend.
"I think it was a little bit rusty but in saying that we managed to set up a few tries just from running decoy lines. He [Ma'a] is a dangerous player, and it's just about finding the space between us two. Hopefully we do that this week."
The fact that his final match is at Eden Park will heighten the sense of occasion for Williams, the controversial code-swapper who had finally won over the sceptics this year with his consistently high-quality play in the midfield. He played only a bit-part for the All Blacks during the World Cup - he came on as a substitute against Australia in the semifinal and was promptly sinbinned for a shoulder charge on mate Quade Cooper.
And, although he won't be involved with the rest of the Rugby Championship, he will always have a Super Rugby title to his name.
"That's something I'll look back on, how we suffered all through the year and came from nowhere as a team and now we're forever going to be known as Super 15 champions so that's pretty special."