In a week where the minnows have stood up to be counted, the All Blacks provided a reminder that their depth has immeasurable value.
Williams was the most influential part of a bench that collectively turned the tide against a Pumas side that led 16-12 with 25 minutes to play and not through blind luck.
On the biggest stage of all, in front of a record World Cup crowd of 89,000 fans at Wembley, Williams provided the angles and the muscle to shift the momentum and bend the defensive line.
He replaced Ma’a Nonu in the 46th minute and before the dreadlocked one had reached his seat, Williams was throwing himself into the melee.
It was a performance that will raise the selectors’ eyebrows as they ponder their backline in the coming weeks.
Now the All Blacks know how difficult this World Cup is going to be when they get to the sudden-death phase next month.
Their 26-16 victory over Argentina wasn’t comprehensive, or terribly convincing, but a win is a win and for that all New Zealand rugby fans will be thankful.
Their campaign to retain the Webb Ellis Cup is finally under way and they required a fast finish to get them home.