So, Justin Langer, about that tactic of getting bowlers into their fourth spells, then… On the eve of his Test debut, in what had otherwise been another horizontally laidback press appearance, Jofra Archer had suddenly fired in a verbal bouncer that was every bit as out of the blue as the languidly launched missiles that exploded on the Lord's Test.

Responding to Langer's pre-match "curiosity" about how his body and mind would hold up in a format notorious for grinding down quick bowlers, Archer's answer dripped with red-ball nous and Test-match readiness, not to mention a confidence that no ordinary Test debutant could have summoned at such will.

"I've played a lot more red-ball than I have white-ball. I do think it's my preferred format," he said. "I've bowled 50 overs in one game already for Sussex and I'm usually the one bowling the most overs anyway. I think Justin Langer has another thing coming."

And sure enough, Archer could hardly have predicted more accurately the day's astonishing scenes had his thoughts been recycled from one of his four-year-old Tweets.

Archer was already 25 overs into his work for the innings, and armed with a ragged old ball that was four overs from completing its 80-over lifespan, when we finally discovered what a silken, effortless, natural-born quick bowler can achieve when he decides the time is ripe to bend that back, and go from effortless to effort-full.

Comparisons are odious when the action is as raw and visceral as Archer made it. The historian David Frith, who witnessed Frank Tyson in his pomp in 1954-55 as well as every great West Indian fast bowler from Wes Hall to Ian Bishop, rightly pointed out that Archer is his own man, with his own methods, and moreover he was bowling within his own context.

The pitch, the conditions, the emotions, the opponents - all of these differ from one great spell to the next, meaning that Harold Larwood at Adelaide in 1932-33, or Jeff Thomson at Brisbane in 1974-75, or Allan Donald at Trent Bridge, or Michael Holding at The Oval, can only really stand as testament to their own brilliance, bullet-points in Test cricket's extraordinary history, or bullet-holes if you prefer.

But what we witnessed, in the context of the recent Ashes rivalry, was a passage of play as savage, compelling and potentially series-turning as that moment when Mitchell Johnson first slipped his handbrake at Brisbane in 2013-14. In a searing eight-over spell at the end of a 29-over innings, Archer reminded us that there's a world of difference between run-of-the-mill quick bowling and furious, rip-snortingly rapid head-hunting.

"I've got massive admiration for Jofra," said a mildly chastened Langer, who insisted that his point about Archer's stamina had been misconstrued. "He's an unbelievable athlete, an incredibly skillful bowler.

"To bowl 30 overs, it doesn't matter if you're Jofra Archer, or Pat Cummins, or Josh Hazlewood, or James Anderson, or [Kagiso] Rabada. It's hard work. And that was my point before the game. His endurance was outstanding today, his skill and his pace. What an athlete, what a great player to have to promote Test cricket."

The catalyst for Archer's onslaught was his return to the Pavilion End, the traditional hunting ground of the senior strike bowler

All throughout his maiden Test innings, Archer had been lurking in Australia's peripheral vision. Pacing, probing, sizing up the pitch, his opponents, and perhaps most of all, his command of a red Dukes ball, the like of which he has barely used in 11 months.

"I don't think Jofra bowled as quick as he can out there," said Stuart Broad at the close of day three.

I think it's fair to say we have seen him do so now...

The catalyst for his onslaught was his return to the Pavilion End, the traditional hunting ground of the senior strike bowler, with its slope back down into the right-hander designed to create doubt in that channel outside off, the very channel in which Steven Smith has been so imperious throughout this series.

Within six balls, Archer had breached Australia's first line of defence, as Tim Paine - watchful throughout his second-fiddle innings - was caught in two minds (and then at short leg) by the one that nipped back off the seam. And like every fast bowler that's ever been born, the thrill of a wicket was all that Archer needed to tip his game into overdrive.

In Archer's next full over with Smith in his sights, he began to purr through his gears - 93mph, 94mph, 94mph - as smooth through his acceleration as a Porsche on the Autobahn. And suddenly Smith found that his extra split-second was no longer there, that his peerless ability to sight the ball on the back foot and point to it mockingly as he left it on the front was redundant.

And then, the first morale-denting strike. A vicious lifter into the forearm, as Smith curled into a defensive ball straight from the hand, unsettled by the line and no longer able to compute the length as the ball chased him like a rogue bludger before leaving him shaking his left arm in agony.

For a time it seemed he might have to retire there and then, his grip compromised, his invincible aura torn, but to his immense credit he popped a couple of pills, accepted some tight binding and took his guard once more. But it was clear that the passive aggression with which he had dominated England for three innings was not coming back - at least not here, not now. This was fight-or-flight mode, and again to his credit, Smith chose the former.

Consecutive bouncers, consecutive hooks - like KP against Lee at The Oval in 2005, but without the soaring upshot, as the first skimmed out of Jonny Bairstow's reach for four before the second plugged behind square for the single. And then, a scorcher, sizzling into the gloves at a scarcely believable 96.1mph … handbrake not so much slipped as torn clean out of its socket.

But the coup de grace was still to come. Another bouncer, another less-than-confident hook for four … and then the sucker punch. An exquisitely awful moment of pure sporting theatre, as Smith was slammed on the side of the neck by another ugly, incredible, spiteful snorter, and felled in the same instant.

The reaction around Lord's was stunned bewilderment … much like Archer's as well, who initially turned on his heel, his objective for the delivery achieved, before realising he needed to join the loose melee that had formed around the stricken Smith, who did at least - in removing his own helmet while spread-eagled on the deck - telegraph the fact that he had not been laid out cold.

An uncomfortable hush descended as the physios of both teams rushed out to attend to Smith, punctuated by a few boos from the witless few who still believe he deserves to be judged for his actions in Cape Town rather than his incredible feats both here and at Edgbaston.

And though he left the field without assistance, it was still a surprise to see him returning to the middle, to yawn into a succession of devil-may-care fours that inched him within touching distance of his third century in as many innings.

It wasn't the same batsman who had left the crease some 45 minutes earlier, however. For starters he ended up being pinned lbw, offering no shot as Chris Woakes curled one back into off stump - the holy grail dismissal that England had begun to believe was a myth in this series.

"It took a serious spell of fast bowling from Jofra to get Steve out of his bubble, because so far in the series he has been incredible," Woakes said. "I'm sure it was incredible to watch because it was incredible to be a part of it on the field and thankfully, having seen Steve on the balcony, it looks like he's okay which is obviously good news."

Smith's return to the middle, Langer joked, had come about because he had protested he wouldn't be able to get himself onto the honours board if he stayed sitting in the dressing-room. And though he failed in that objective, the drama had been so absolute that, for once in this series, his extraction from the crease counted for less than the fact that he had returned to it at all.

Andrew Miller is UK editor of ESPNcricinfo. He tweets at @miller_cricket