"The West Indies T20 side is one of the best in the world and we know at any time they can turn it on," said the returning Black Caps captain.
While their historical accolades back up Williamson's viewpoint, the West Indies' talent suggests otherwise.
Just three players remain from their 2016 Twenty20 World Cup winning side, replaced by a competent, but less powerful bunch.
Gone are the likes of Johnson Charles, Marlon Samuels, Dwayne Bravo, Andre Russell and Darren Sammy, replaced by a group of capable strokeplayers who have yet to prove that they can score as quickly as the format demands.
Veteran West Indian spinner Samuel Badree is understandably confident in his teammates' abilities to support Gayle.
"We've got some quality batters all the way through. I don't think we're reliant too much on him."
The numbers disagree.
Of their top six batsmen, only Gayle has a strike rate above 113. In a format where 120+ is a minimum requirement for international batsmen, the West Indies top order is flatly not up to standard, especially with the bullocking Evan Lewis also unavailable.
Chadwick Walton has yet to shine in any format, Andre Fletcher has a strike rate of 106 in 32 innings, and Shai Hope - he of the incomprehensible ODI strike rate of 68 - has somehow ended up in the T20 side.
While their bowlers are solid, and Carlos Brathwaite provides a mighty presence at No7, it feels like the West Indies top order will go only as well as Gayle does.
Comparatively, New Zealand's top order is well balanced. Their top five from the first T20 all possess a strike rate of 120 or greater, as does Williamson, who has missed the last three games due to an enforced break to stay rested.
While loathe to miss international cricket, Williamson can see the benefits of staying fresh.
"It was nice to have a few days at home - a planned thing, so you try to utilise it. Perhaps it wasn't a bad thing. It's pretty exciting to get back with the guys.
"One of the bonuses of having guys have small breaks is that we're able to give other guys gametime at the highest level, and that does help with the depth. We're seeing that guys are coming in and performing well."
Williamson will slot back in to a top order which received contributions from Colin Munro (53) and Glenn Phillips (55) in the opening T20, and that multitude of options is why the hosts are heavy favour-ites to continue their run.
It is a winning streak which could soon be historic. Only once before has a touring side lost all eight games in New Zealand - Bangladesh's tour a year ago - and the West Indies can join that unwanted group if they lose their remaining two Twenty 20 clashes.
So, while the Windies are up against it, the last word goes to Badree, who succinctly summarises what makes Twenty20 cricket such a lottery.
"We're confident and optimistic of a good game - anything can happen on any given day."