Bairstow's red-faced roar as he reached three figures in the broiling heat of Colombo, bat cast aside and fists pumping the air, was one of the most expressive celebrations in recent memory and spoke volumes about the meaning attached to his battling 110.
In terms of the third Test against Sri Lanka, and England's hopes of a whitewash, it was a vital innings and formed the spine of a promising stumps score of 312 for seven, but for the 29-year-old it meant so much more.
An unfortunate ankle injury forced him out of the opener in Galle where a brilliant debut from Ben Foakes, his stand-in as wicketkeeper-batsman, resulted in his unwelcome omission when passed fit in Kandy.
— England Cricket (@englandcricket) November 23, 2018
With Foakes' smooth glovework guaranteeing an extended run in the team, Sam Curran's side strain forced Bairstow to settle for a recall as a specialist batsman in the vexed slot at number three.
Five others have batted there in 2018, with Tom Westley and Gary Ballance also unsuccessfully pitching for the job in the two years since Joe Root scored England's last Test century from first wicket down.
Bairstow has never courted the role, much happier to reside in the lower-middle order and devote equal attention to his keeping, but fate may have revealed it fits better than the gloves.
He got off the mark first ball with four through extra-cover, swatted a gloriously dismissive six over midwicket, swept tidily and punished errors in length. When he eventually departed, bowled leg stump by Lakshan Sandakan, he did so with a point proven and his future seemingly sewn up.
If he nursed any sense of injustice at being overlooked last time out he channelled it in just the right way, knuckling down for 186 deliveries and sharing in crucial stands of 100 with Root and 99 with Ben Stokes.
While the psychological demands of his knock were most obvious in the wide-eyed yell that accompanied his 100th run, the physical toll was apparent much earlier.
He battled with the apparent discomfort of cramp throughout the latter half of his stay, grimaced his way through several sweeps and runs but never dialled down the intensity of his focus in stifling conditions.
The day had started with Root extending his winning run at the toss to eight in a row, batting first for the third time in a row on the trip.
England lost both openers in the first hour, Rory Burns stepping away to cut Dilruwan Perera at the cost of his off stump and Keaton Jennings turning Malinda Pushpakumara obligingly to leg slip.
Brought together at 36 for two, Bairstow and Root proceeded to make a steady century partnership either side of lunch.
Frustrated by the Yorkshire duo and eager to strike again, Sri Lanka wasted both DRS reviews in the morning session – a caught behind shout off Bairstow's elbow and a poorly-judged lbw appeal against Root.
That meant no referrals were left when umpire Chris Gaffaney turned down a plumb lbw that would have landed Stokes a 14-ball duck or when Bairstow was trapped in front on 102.
Sandakan went at more than four an over but continued to check English progress, persuading Root to top-edge a sweep for 46 and having Stokes caught at slip. The all-rounder's 57 was a turbulent knock, including several moments of indecision, four boundaries and two cracking sixes.
A return catch from Jos Buttler gave Sandakan a fourth victim, with Perera accounting for Foakes late on. Moeen Ali was dropped at slip on two and 17, then overturned two lbws as he somehow survived to stumps alongside Adil Rashid.