Just in case his team was becoming complacent with a record of 24 wins in 25 matches under their Aussie boss, and two out of two in the current Six Nations Championship, Jones used the “symmetry” of this week’s trip to Scotland –also the fixture with which he began his England tenure – to call up the clips of his very first training session with the squad in January 2016. It still shocks him now.

“I remember after the first training run, I was thinking ‘Goodness me, what have I got myself into here?’,” Jones recalled yesterday after naming his team for the Murrayfield match, with Nathan Hughes’s much-trailed return at No 8 as the only change to the starting line-up.

“They [the England players] weren’t fit. They wanted to play a system of attack, a system of defence and I thought ‘this is going to be hard work’. After 20 minutes, [they were] just shot. Couldn’t run any more. Not fit enough. And the basics of Test rugby is physical condition. You’ve got to be fit enough to play. We’ve been looking at data now and, conservatively, we’ve improved 40 per cent. And we’ve still got another 20 per cent to go.”

England head coach Eddie Jones at a training session at Bagshot. Picture: Getty

Considering the England class of 2016 were in mid-season with their clubs, and only a matter of weeks after the majority had participated in a World Cup, albeit unsuccessfully, the degree to which Jones decided they were off the global pace is astonishing. But Dylan Hartley, the captain who will tomorrow become England’s second most-capped player, with 92 Tests – behind only Jason Leonard on 114 – willingly accepted Jones’s assertion.

“I can’t remember the actual session but I remember the period and we talked about it this week,” said Hartley. “If you compared the GPS statistics from then with now it would be unbelievable. I’m a hell of a lot fitter than I was. And there’s still room to grow.

“Everyone thinks they are fit. But are you fit for purpose, fit for the purpose of rugby? That’s what Eddie instilled. He said: ‘You may be able to run and lift but can you get back off the floor?’ We’re better rounded to play rugby now.”

As such, the players are under constant scrutiny with Jones remarking: “The only place we don’t have cameras on them is in their bedrooms.”

And he points to the number of matches won in the last 20 minutes by the world-leading All Blacks. Apart from the solitary loss in Ireland last March, when England were unable to change pace, Jones’s team have been superb at either closing out or overhauling opponents at the last  knockings.

“A heatwave might come through Murrayfield this Saturday,” said Jones. “Or it might be freezing where the ball gets harder to move. [Referee] Nigel Owens might have one of those days when he wants to be centre stage and it might be a tight old game. What we want to know about ourselves is we can tough it out in any  situation.”

Jones was uninterested in responding to his Scotland counterpart Gregor Townsend’s accusation of  England flouting the offside law, which is hardly news to the world’s rugby aficionados.

Jones was keener to cite Manchester City as a team unfussed by whether they are playing home or away, but he did mock comments by Scotland’s New Zealand-born prop Simon Berghan, before a later clarification. “I thought that was one of the most humorous parts of the week,” Jones said. “The New Zealand prop saying how much he hated the English then being told to go in and apologise. I laughed. It’s been a pretty tense week so it’s nice to have those laughs.”

England's poor fitness shocked Eddie Jones at start of reign