At times this Wimbledon fortnight has felt a bit like a grand, Pimm’s‑sozzled Viking funeral. Here we have the ghost of Roger, reincarnated as royal box candy, rolled out to make the crowd coo and clutch a hand to its flushed throat one more time. Here we have another instalment in the extended farewell of Andy Murray, an athlete by now almost entirely held together with pins and staples, still gamely hobbling off in pursuit of that vanishing horizon.

The sense of passing greats, heritage exhibits, the stars falling from the skies: all of this is in its own way deeply Wimbledon. But the sun also rises, and Wednesday afternoon there was a thrilling sense of future shock about watching Carlos Alcaraz and Holger Rune – 20 years old and born just six days apart, doubles partners at the age of 13, and now the world No 1 and No 6 – produce an opening set on Centre Court not just of startling quality, but of new forms, new shapes, new energies. New noises even with the volley of Danish voices from the box, the vamos Carlitos from the bleachers.

This was the first time two men’s singles players younger than 21 have contested a Wimbledon quarter-final. Alcaraz is clearly the more fully formed talent right now, a player with an air of outright historical ascent about him already. There was clear air between the two as Alcaraz eased through the endgame of this 7-6 (3), 6-4, 6-4 victory.

But there was still something startling about the spectacle of that opening hour. Perhaps in 15 years the meeting of these two grand talents may feel as deeply familiar as the old fuzzy green titans.

For now it felt bracingly fresh. Alcaraz in particular is already a phenomenon. No 1 in the world when he was still a teenager: this is mind-blowing stuff. There is no rawness here, just something whisperingly high spec, to the extent watching him progress through each successive grand slam tournament is like unboxing the latest iPhone, something perfectly pre‑configured, intuitive, refined to perfection.

He has one grass court title to date, Queen’s Club last month. It doesn’t really matter. The surfaces increasingly elide into one. And Alcaraz is a postmodern player with an all-court, portable game: mobility, power, angles; yeah, why not just have it all.

Carlos Alcaraz shows off his full array of shots in beating Holger Rune. Photograph: Tom Jenkins/The Guardian

And for all his shot-making creativity, his showman qualities, Alcaraz is above all utterly controlled, and all the better for it. In the distant past tennis teenagers would arrive at this stage unformed, raw, and utterly vulnerable. Boris Becker won Wimbledon while still resembling an eager, confused schoolboy: pudding-bowl hair, scratchy shirt, massive squelchy trainers, whirl of unbound groans and yells.

He came back and won it the next year, still a teenager, styled and slicker but still oddly startled, already being chewed away at by fame, new things, the unfiltered gaze, Bonking Boris and all the rest of it.

Alcaraz is already out of reach of these things. He was born into this life, a prodigy from inside the machine, emerging fully formed and wised up. Even on court you can sense at times his way of curating his own imagery, the brilliant shot-making, the cool celebrations, a player who is innately aware of how this thing is consumed and presented now. Too often those tennis teenagers were consumed by the light and the heat. Alcaraz is the light.

This was basically a fight from the start, a match that began like we were already in some sweat-drenched, eye-boggling midnight tie-break. Alcaraz went to advantage in his own opening serve game with a rally that ended with Rune running into the net. It took five minutes to get to 1-0 up.

With 31 minutes gone and the score 3-3 Rune unfurled an extraordinary whipped forehand winner of his own and turned to his box, who were all shrieking and cheering, already lost in the day.

In between the bravura moments Alcaraz just kept racking up the points with the same unrelenting craft and intensity that would see him win the second set without a single unforced error. He made it 4-3 with a leaping cross-court winner having just appeared at the net without any obvious effort, moving so sweetly it felt as though the net was coming to him.

Elite tennis players are such rare full-body specimens, athletes whose talent must be focused not just in their feet or their hands but in every limb, every joint, tennis fingernails, tennis toes. Alcaraz has that total athleticism to a startling degree. He is just all bounce, all spring, all flex from those extraordinary thighs.

At 6-5 down Rune produced his own astonishing sequence, a blur of drop shots and spanked winners. And of course, 57 minutes in, it went to a tie-break. There was still a playfulness here, as Alcaraz went 2-1 up after a rally that involved slice, misdirection and raw power. But by now he was running on a deeper energy, taking the set with a stunning, reaching backhand return, yodelling up to his box. We will see this again from both men. For now it felt like something new; and in Alcaraz’s case, already close to its final form.