has embodied New Zealand cricket for the last six years but, as he threw his head back in disgust at his shot on the third afternoon in Leeds, it was hard not to wonder about his future.
Perhaps Williamson is also wondering. After all, the first day of this Test was the anniversary of his team's triumph in the inaugural World Test Championship
. But in the 12 months since, Williamson has not reached 50 and New Zealand have not won a series. The rise was gradual, the fall has been sudden.
Williamson was in the form of his life only 18 months ago, racking up 639 Test runs - including two double-hundreds - in four innings in the 2020-21 home summer. But by the end of the season, he was struggling with an elbow injury that has been a constant, nagging source of frustration ever since.
His injury essentially arose from "overuse", according to his head coach Gary Stead. In the same vein as Steven Smith, Williamson batted so often and for so long that his elbow could no longer cope. For some time, his nets sessions were sparse, and limited to a maximum of 20 minutes each.
Williamson's elbow has caused him to miss a huge amount of cricket, including the entirety of New Zealand's most recent home summer. He has tried to find a balance between playing and rest but it has proved a struggle: asked about how to manage it earlier this year, he joked that the easiest solution would be to "cut it off".
And while he has been away, something seems to have gone missing from his batting. He has never been an ultra-aggressive T20 batter but at this year's IPL he resembled a man out of kilter with the modern game, averaging 19.63 with a strike rate of 93.50 despite opening the batting for Sunrisers Hyderabad, who had made him their captain and highest-paid player.
In this series, he seems to have lost faith in his judgement outside off stump, as showcased by an awkward half-dab, half-leave off Jack Leach shortly before his dismissal. "There's a slight hesitancy," Mark Butcher said on Sky. "The brain is whirring away: it's not natural at the moment for him."
He started slowly on Saturday, creeping to 9 off 43, before a flurry of boundaries which served a reminder of his crisp, fluent best: an extra-cover drive then a leg-side whip off Ben Stokes, a back-cut off Leach and a swivel-pull through midwicket off Stuart Broad.
But then Matthew Potts set him up
, bowling four balls from identical release points before jumping wider for the fifth. The ball angled in then nipped away and Williamson was pushing away from his body, feet stuck on the crease. It was the third time Potts had dismissed him in four innings in the series, one which will end with an aggregate of 96 runs and a further dent in his record in England
Williamson ripped his gloves off furiously, muttering in frustration under his breath. He has had so much going on in the last two months: a lean run with the bat, long-haul flights to be at the birth of his second child, his elbow nagging away in the background and then a positive Covid test which caused him to miss the second Test at Trent Bridge.
And while every small moment seems to have gone against New Zealand, some of Williamson's decisions have been hard to justify: Ajaz Patel will end the series having bowled just two overs while Leach, a similar bowler with a slightly Test worse record, has thrived at Leeds after being backed to the hilt by his captain on a dry pitch that has turned from the first evening.
Williamson "obviously works extremely hard," Trent Boult
said. "He's been in and out of the side over the last wee while and I'm sure he'll be frustrated with how it went today. That's the game we play: the guy didn't try to get out, it was just down to good bowling, a bit of pressure and the situation that he was under.
"He doesn't get too high or too low, really. I'm sure he'd love to be playing every series and not missing out on tours but he's a big part of our side, a big leader. You don't get too much out of him but he's got a lot of passion for the side and where it wants to go."
A year ago, Williamson was front and centre of New Zealand's coronation, unbeaten on 52 at the Ageas Bowl when Ross Taylor
hit the winning runs. Now, he is the personification of a side that seems to have lost its sense of common purpose and direction and is staring down a 3-0 whitewash.
The murmurs about his role as captain have already started. The prominent broadcaster Simon Doull has been among the advocates for him to step down; Tom Latham
, his heir apparent and regular deputy, had done little to push his own case on this tour but his punchy 76 was an overdue return to form.
There must have been times in this series when Williamson has looked at Joe Root, his old opposite number and former Yorkshire team-mate, with a sense of longing. So recently weighed down by the captaincy - as a person, if not a batter - Root has seemed liberated in this series; with New Zealand's next Test at least five months away, perhaps this is the time for Williamson to liberate himself.
Matt Roller is an assistant editor at ESPNcricinfo. @mroller98