Buttler's maiden half-century at full international level could not keep England competitive as New Zealand outplayed them for a 55-run win which made it 1-1 in a three-match series. But it was another demonstration of the 22-year-old's precocious talent, as he followed up successive 50s last week in England's two warm-up matches against a New Zealand XI.
It is a moot point whether it was the intention of England's limited-overs coach Ashley Giles - when he nominated Buttler to keep wicket - to instil extra confidence. But the dual role, and perhaps the certainty of selection, is clearly agreeing with him. "I feel a lot more comfortable, a lot more myself, and I'm really enjoying the environment and thriving off it," said Buttler.
"I'm really enjoying the wicketkeeping, and it's an area of my game I'm really developing. It's something I want to do more and more."
He does not know whether he or Jonny Bairstow will be entrusted with the gloves for the one-day international series which follows almost immediately after the Twenty20 decider in Wellington.
"I'm not sure yet," he added. "I'm just looking to this game on Friday - a huge one for all of us. It's a 'final', and set up brilliantly in Wellington."
It does not appear likely either that Buttler will be pushed up the order from number six, where he hit nine fours and a towering six in Tuesday's 28-ball 50 at Hamilton's Seddon Park.
"We're very happy with our plans and the way we're going, and we've got an adaptable order anyway," he said. "At certain times it chops and changes, but we'll be looking to stick to the formula we have that's been successful and put it into practice again."
Mitchell McClenaghan caused England's early stumble, with two wickets in two balls - including the dangerous Luke Wright for a golden duck. The Kiwi left-armer senses that the tourists will remain vulnerable.
"I think they got in their own heads, from what I heard," he said. "We just do what we do and put some pressure on - and if they make mistakes then it plays into our hands."