The Premier League reopens for business on Saturday for perhaps the most mentally and physically demanding six weeks in its history.

Forty-four days in which six of last season’s top seven will play 13 times across all competitions, condensing around a quarter of their season into just over 10 per cent of the available calendar.

“Insane. Wild. Absolute madness,” said Simon Brundish, a consultant sports scientist for various clubs and players. “Crazy,” agreed Antonio Conte, the Tottenham manager.

“When we start talking about it, I really get angry,” added Liverpool manager Jurgen Klopp who, in likening the situation to climate change, declared that “we all know we have to change” but evidently feels utterly powerless to shift football’s governing bodies.

And all this following last season’s sharp spike in Premier League injuries. But there is another point, too.

The next six weeks are also very likely to be decisive. They represent a positive opportunity for those clubs who can grasp it. With the World Cup taking place in Qatar between November 20 and December 18, Christmas will loom at the end of this period and recent history is emphatic in underlining how the order at that time of the year is so often defining.

Liverpool apart (in 2013-14, 2018-19 and 2020-21), the team top at Christmas have won the Premier League in each of the past 12 seasons. The fate of those clubs bottom at Christmas has generally also been set with regard to relegation.

“This is the moment you understand who are contenders and teams competing for Champions League positions,” said Conte, hinting at how, for all their public grievances, the managers also know the importance of what now follows. It is also a huge moment for the vast backroom teams.

The psychologists must keep the players focused on their clubs despite a looming World Cup, while the numerous doctors, medics, physiotherapists and sports scientists will be charged with maintaining the players physically in the face of an unprecedented schedule.

It is not just the volume of games – other seasons can be busy at this point – but the fact that, for the big clubs, it is almost exclusively Premier League and European fixtures.

“There’s no opportunity to play the kids – it’s unique,” said Brundish.

An ability to navigate individual game-time during a season was one of Sir Alex Ferguson’s less celebrated but most important managerial qualities.

Former staff tell stories of how he would map out the campaign on a big board in his office to the detail of knowing which exact changes he might make for particular games from months in advance. It was sometimes for specific tactical reasons, but with everything geared to optimising a player’s productivity while minimising their risk of injury. This was largely done by intuition and feel.

There has since been an explosion of statistical data and, while much of that relates to recruitment, a lesser-known element is how it informs when players are at risk of injury and should take preemptive action.

“We have 15 years’ worth of GPS data – total running, high-speed distance, sprint distance and the consequences to a players’ physiology,” said Brundish. “Each player will be different. It is the growing industry from a software perspective.”

The rewards of getting it right have never been greater

The data even extends to advising exactly when a particular player’s central nervous system will have recovered following the stress of a game. Liverpool now work with an American artificial intelligence company called Zone7 which has created computer algorithms that both detect injury risk and recommend preemptive action.

Most of the clubs are moving in a similar direction and the quality of their work in this area will be especially critical over the next six weeks. The basic rule of thumb is that playing with three clear days between matches – such as Saturday and then Wednesday – is safe and manageable for most players. However, playing with only two clear days between matches – such as Wednesday and then Saturday – brings a significantly elevated risk.

It all means that players will often be a day short each week and that risks and compromises are unavoidable, especially for those players who record a high number of sprints in a game.

It is likely to be especially challenging for the smaller clubs, partly due to the size of their squads, but also because they will typically have fewer players with a history of absorbing high numbers of minutes. This is something that is now carefully examined during the recruitment process.

All the meticulous planning, which has been going on since the fixtures were first confirmed in June, has been further complicated by the postponement of matches as a mark of respect to the late Queen.

Conte said yesterday that he would not take risks and, while the room for manoeuvre has never been more limited, the rewards of getting it right have also never been greater.