AL THANKS TO HIM: Mikel Arteta has Sir Alex Ferguson to thank for outrageous £20m-a-year Arsenal contract

The Rooney Rule is an important policy adopted by the National Football League in the United States that requires professional teams to interview diverse candidates for senior coaching, operational and front-office positions.

Originally established in 2003, it has been one of sport’s most important developments. Infinitely less important is another Rooney rule, established in 2010 by Sir Alex Ferguson, who wrote this in his 2015 book, Leading.

“I told them (the Manchester United owners) I did not think it fair that (Wayne) Rooney should earn twice what I made and Joel Glazer immediately said: ‘I totally agree with you but what should we do? It was simple. We just agreed that no player should be paid more than me.”

To be fair, not many managers get into the position of strength that Sir Alex enjoyed in 2010. Pep Guardiola, possibly Jose Mourinho in his pomp. And now Mikel Arteta.

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For as long as he stays at Arsenal, the manager will be the highest-paid employee. The most conservative estimate of the value of his new contract, which runs until 2030, comes in at around £20million a year.

Bukayo Saka is believed to be the highest-paid player, his recent extension taking his wages into the £18m-a-year bracket. Declan Rice will soon join him there.

No one can possibly begrudge Arteta his phenomenally lucrative deal. He has reestablished Arsenal as a true powerhouse of domestic and European football.

He has become a more measured figure in the technical area, is extremely bright and has a very personable manner. But the figures involved are ridiculous. And that, of course, does not just relate to Arteta’s new contract, which some publications believe to be in the £25m-a-year ballpark.

Is Mikel Arteta the best manager in the Premier League? Let us know your pick in the comments section.

The Manchester City case will not only undermine the integrity of this Premier League season, it undermines the integrity of a couple of decades’ worth of seasons. How will that affect the next broadcasting deal, which provides the financial lifeblood of the Premier League?

Managers’ salaries count towards the Premier League’s financial regulations, which now take the form of Squad Cost Ratio. Arsenal are not anticipated to have any issues on that front but others well might. Nottingham Forest are said to be paying Oliver Glasner around £12m a year.

And while you definitely should not begrudge Arteta or Glasner, or any other manager, their preposterously handsome pay packets, the money does have to come from somewhere. Eventually, it comes from the fans.

Envy is not a good look but when you see a manager being given a deal that pays him not far off £500,000 a week, you have to wonder if the elite game is heading in the right direction. Arteta’s most recent result - a chastening 3-0 defeat at Brighton - has no relevance, but consistent excellence is hard to maintain.

In recent years, the accounts of Premier League clubs - well, those apart from Arsenal, City and Liverpool - are festooned with pay-offs to sacked managers and their staff. And the money comes from you. From your TV subscription, from your replica shirt, from your ticket, from your over-priced food and drink.

For now, Arsenal supporters will not care about that. What is important is that Arteta and the club seem a perfect match and the manager has committed himself to the ‘project’ for another four years, at least.

It is developing into a dynasty. But there was a time - well before Ferguson’s Rooney rule - when managers were modestly paid, when there was a view that the talent that mattered most was out on the pitch.

We can safely say that time has gone.