LET’s get ready to rumble, as my maw used to say when she was feeding us on an exclusive diet of beans.

The hype over this weekend has produced more hot air than the cowboy tea-time scene in Blazing Saddles. But I am drawn to matters on the sidelines rather than on the field of play or in the ring.

There will be those who drool over Barts v Broony. There may be others who look with febrile anticipation to Golovkin v Brook. I am fascinated by Pep v Jose.

There is an element of farce of the match-up between Scott Brown and Joey Barton. It’s all trash talk and, on occasion, even trashier passing. Golovkin and Brook will be brutal, but it is strictly business.

It is Mourinho and Guardiola, though, who stage the main event. The Manchester derby was recently as relevant to the wider world as the precise cost of the Kazakhstani TV rights for Coronation Street. United fans and players looked to Liverpool for that authentic derby tang of spittle-flecked venom. But no longer. The battle is on the doorstep. And the stooshie is on the sideline.

Pep and Jose co-exist as easily as Donald Trump and reason. If the latter match-up has the capacity to go soddin’ nuclear, then the former has more than enough to fuel a very personal, nasty spat. The reasons for the antipathy have been the subject of more articles this week than the time Joey Barton sensationally said something uncontroversial. And what a five seconds that was.

But the very existence of the Pep/Jose stooshie is worth investigation. At one level, it is hardly unusual. Football is full of people who do not like other people.

A casual chat with a pleasant former manager will suddenly alight on another amiable former manager who spends his time raising money for orphanages and knitting socks for our heroes at the front. There will then be a verbal explosion so catastrophic that one waits for a mushroom to form before proceeding to the precise reason for the enmity.

It will turn out that Manager A hates Manager B because of an altercation over a missed offside call in a testimonial match some 35 years earlier. Any attempts at reconciliation by colleagues, wives and UN officials have been brushed off with the sort of contempt only previously shown by readers to a Saturday sports column.

These enmities are normally private. The managers will shake hands cordially, may even schmooze on screen but they burn internally with all the heat of that pie left in the microwave for an entire Easter weekend. It can happen.

The beauty of Pep v Jose, and it is a terrible beauty, is that it is unashamedly public and forces one to pick sides. As Tolstoy memorably observed in Anna Karenina, his study of CSKA Moscow’s first female coach: “All happy managers are alike; each unhappy manager is unhappy in its own way.’’

Both Pep and Jose are restless types, who live far from contentment. They are both obsessed, of course. Great managers need obsession the way a bus driver needs a licence. They share, too, a compulsion to win. Much has been made of Pep, the artist. But he plays to win.

Their difference is one of approach. Pep has sought to re-invent the game, Jose merely reshapes it. It is the Portuguese, though, who has enjoyed the more unlikely victories. One may have gasped in delight at Pep’s Barca but, remember, Jose has won the cup with the big lugs with Porto and Inter Milan. The latter triumph in 2010 is all the more sweet for Mourinho for his confounding of Barca and Guardiola in the semi-finals.

This was the master manipulator, the whirlwind winder-up at his irrepressible best. It was Mourinho as the pragmatic, detailed schemer. He faced what seemed like insuperable odds and he came up with a plan that took the game and the tie from Barcelona.

Pep and Barca won the big one the next year but that wound remains. Others fester. And not just on the Catalan’s side. Mourinho lives on resentment and occasionally invents causes for it. Guardiola bristles with antipathy towards his adversary.

They will stand on the sidelines at Old Trafford, separated by their differing beliefs, their approaches and their contrasting styles. But they share both a dedication and the necessary attributes of all great managers, that is, the ability to make multi-millionaires play for them. There will be enough football on show at Old Trafford to fascinate the most casual of football supporters. There is Kun Aguerro, Kevin De Bruyne, Wayne Rooney and … Zlatan Ibrahimovic. The Swede dislikes Guardiola as much as he likes himself.

But the fascination lies in the managers and how they try to secure victory and how they react to the result. The cameras will regularly drift from the pitch to linger on the sideline where Pep and Jose will certainly suffer, perhaps celebrate.

The cult of personality has generally been an unwelcome addition to modern football, particularly when managers assume greater importance than world-class players. But Old Trafford today is an exception, where one can welcome the attention on two extraordinary characters.

This is a clash that does not just have the semblance of enmity or rivalry but absolutely reeks of it, sourly and powerfully. Like tea-time at the MacDonalds on beans night.