Verstappen dominated the 2023 season, setting numerous records en route to his hat trick of championships and joining an exclusive club of what is now 11 drivers to have won three titles or more.

For Red Bull, the season was almost perfect, as it won 21 of the 22 grands prix, with its only blip being in Singapore when the team opted for the wrong setup from the outset with the RB19 from which it failed to recover until it was too late.

Verstappen salvaged fifth in that race, but it motivated what Horner feels was one of the most remarkable weekends from his driver who was quickest in all three practice sessions for the following grand prix in Japan, and nearly six-tenths of a second faster in qualifying than nearest rival Oscar Piastri in his McLaren.

As for the grand prix, Verstappen’s pre-event prediction to Horner fell agonisingly short on a day when Red Bull clinched back-to-back constructors’ championships thanks to the Dutchman’s victory over McLaren’s Lando Norris.

“What was interesting for me, out of that event (in Singapore) was…not frustration, but it hurt Max not winning,” recalled Horner.

“By the time he arrived in Japan, he was so motivated, probably the most motivated I’ve seen him over the last few years, to really lay a marker down in Suzuka.

“I travelled with him from Tokyo to Suzuka, and he said, ‘I’m going to win this race by 20 seconds’.

“His very first lap in practice, on a set of hard tyres, was just stunning. It was two-and-a-half seconds quicker than anybody else. I think his first flying lap would have put him third in that session.

“It was an insane performance all weekend, and he won the race by 19.4 seconds. I said to him, ‘You nearly made the 20 seconds’, (and he replied) ‘I had a blue flag and it cost me half a second on that last lap!’.

“Honestly, that was one of the strongest displays I’ve ever seen from a driver throughout that weekend.”

In a season when Verstappen was utterly ruthless, winning 19 of the 22 races, and the majority of those with consummate ease, such as in Japan, it begs the question as to whether the 26-year-old ever fully extended himself.

Horner insisted there were “numerous occasions”, such as on the final lap in qualifying for the Monaco Grand Prix when he delivered a millimetre-perfect run to deny Aston Martin’s Fernando Alonso pole position by just 0.084secs.

In a race, Horner said there were “certain periods”, adding: “But the way these races run, so much of it is about the conservation of tyres.

“So where he had the inner confidence was somewhere like, Austin, where Lewis (Hamilton) was hustling him really hard in the early part of the race, and he just had the confidence -‘Don’t kill your tyres, don’t kill your tyres’ – and then it came to him, with a stint length and so on.

“Having the mental discipline to be able to deal with that and soak up the pressure, so yes, he did extend himself at numerous points during the year, even as early as Saudi Arabia.

“There were question marks as to whether he was going to drive in Saudi because he was so sick. The week before he picked up a nasty cold and stomach bug, and he was really in bad shape, but the way he bounced back, and his Saudi race, again, massive.”

Arguably, the most crucial race was the Miami Grand Prix in which Verstappen started from ninth on the grid behind pole-sitting team-mate Sergio Perez.

Verstappen went on to overtake Perez in the closing stages and win by just over five seconds. From there, the former went on to crush the opposition through to the end of the campaign.

“Miami, for me, it was a big turning point,” said Horner. “For Checo, psychologically that was a massive blow for him that weekend.

“So when you look back at the different races, he was remarkable.”