Rob Beasley is the sports journalist who knows better than anyone what makes Jose Mourinho tick.

He had a regular audience with the Special One and they exchanged many emails and text messages.

These are revealed in an explosive new book which is being serialised by Sportsmail and give a fascinating insight into the Manchester United manager's mind.

When you publicly denounce someone as a 'specialist in failure' and a 'voyeur', it is abundantly clear you don't like them much.

What must Jose Mourinho's views on Arsene Wenger be like away from the cameras and microphones? Unsurprisingly, they're even more damning and the gloves have been well and truly off whenever the matter of Monsieur Wenger has been raised.

A couple of times Jose even talked about wanting to physically fight the Frenchman. That's how bitter and basic their rivalry has become over the years.

It's a deep dislike that has festered into one of the longest-running feuds in football, with the pair clashing ever since Mourinho first arrived in England in 2004.

Jose Mourinho has never been able to hide his dislike for Arsenal manager Arsene Wenger

Their feud is one that has festered into one of the longest-running feuds in football

Relations have deteriorated steadily since then and now both men find it impossible to hide their scorn.

In the summer of 2013 Mourinho returned to the Premier League with Chelsea, once again becoming a direct rival of the Arsenal boss. It didn't take long for hostilities to be renewed.

The following January Wenger spoke out about Chelsea's plans to sell star midfielder Juan Mata to Manchester United for £37million.

Asked if he was surprised at the move, Wenger replied: 'Yes I am, because they sell a great player to a direct opponent.'

He then made the point that Chelsea had already played United twice that season so Mata could not hurt them but his quality could hurt teams like Arsenal who had only played United once. 'It opens up again questions about the dates of this transfer window,' said Wenger.

Their rivalry is one which has been brewing since Mourinho arrived in English football in 2004

Wenger and Mourinho shake hands at Stamford Bridge prior to a 0-0 draw in 2005

JOSE MOURINHO: UP CLOSE AND PERSONAL by Robert Beasley, published by Michael O'Mara on September 29 at £16.99

Mourinho saw this as yet more evidence of Wenger's obsession with all things Chelsea but for once he bit his tongue. That all changed the following month.

Wenger had made a thinly disguised dig about Mourinho deliberately playing down Chelsea's chances of being crowned champions because of a 'fear to fail'. It was too much for the ultra-competitive Mourinho to resist, so when he was asked about Wenger's comments he let fly.

'You know, he is a specialist in failure. Eight years without a piece of silverware, that's failure. If I do that at Chelsea I leave London and I don't come back.'

Mourinho had carried out a cold-blooded assassination of his enemy in broad daylight. Inevitably it was too gory for some, who believed Jose's brutal honesty was too vicious and vindictive. Not to him it wasn't.

A few days later he was still pumped up about it all, telling me: 'When Mr Wenger criticises CFC and Man United over the deal with Mata...I will find him one day outside a football pitch and I will break his face.'

Sure enough, a few weeks later Jose did give Wenger a beating.

Wenger was humiliated when Mourinho's Chelsea beat them 6-0 at Stamford Bridge in 2014

The thumping defeat came on the day when Wenger was celebrating 1,000 games in charge

Wenger ducked out of the post-match press conference, insisting the bus was about to leave

MOURINHO VS WENGER COMPETITIVE RECORD Games played: 13 Mourinho wins: 7 Draws: 6 Wenger wins: 0 Advertisement

It was March 22, 2014, the day of the Frenchman's 1,000th game as a manager, and it just happened to be an away match at Chelsea. Final score: Chelsea 6 Arsenal 0.

Wenger was utterly humiliated, so much so that he ducked out of the usual post-match press conference. His excuse was that the Arsenal team coach was about to leave.

Jose was quick to mock Wenger for that, joking with me: 'Next time I lose a game I don't go to the press conference because the team bus is waiting for me.'

No sympathy, no remorse, no regrets. Wenger had become the man Mourinho just loved to hate.

But the war of words between the two became physical in October 2014 at the Bridge

The game is best remembered for an angry shoving match between the pair on the touchline

Mourinho says he told Wenger 'you know I can't react, but I will meet you one day in the street'

The war of words between the pair actually became physical on Arsenal's next visit to the Bridge, October 5, 2014. Chelsea won 2–0 but the game is best remembered for an angry shoving match between the managers on the touchline.

I asked Jose what had happened and he revealed: 'He was asking for a red card and pressing the ref in my technical area. I told him to go back to his area. He pushed me.

'I told him, "Here you do that, you know I can't react, but I will meet you one day in the street".' Now I don't think Jose was ever serious about having fisticuffs with the Frenchman, he was just huffing and puffing and letting off steam.

I gave him the benefit of the doubt on this occasion, even though an article for me with Jose saying, 'Let's sort this out in the street, Arsene' would have been huge.

Wenger has no competitive wins over Mourinho, but did win the Community Shield in 2015

I told Jose this could be a good story to show he took no nonsense from Wenger but I added that I thought it was best to leave it.

Jose took it on board, replying: 'Yeah, yeah, he is in a bad situation for his clean image but if I do what he did I would be dead by the media and the FA.'

Later in the 2014–15 season there was more astonishing stuff from Jose after Chelsea won 5–0 at Swansea. When I congratulated Mourinho he was already looking forward to the next day's clash between Manchester City and Arsenal.

He declared: 'Yes was good, now let's see s*** Arsenal.' We were both convinced City would win but Arsenal won 2–0.

I told Jose they'd actually done a 'Chelsea' and copied his game plan from a year ago and his emailed response left me gobsmacked.

First he joked: 'Mr Wenger gets new 5 years contract' but then he claimed '(One of the Arsenal players) sent me an SMS to say players did themselves, organised themselves during the week. Wenger did nothing.'

Mourinho's Chelsea beat Swansea 5-0 in 2015, but he was more interested in Arsenal's game

When I expressed my amazement he replied that his information was '100 per cent'.

What was undeniable was the depth of Mourinho's dislike for Wenger. That could certainly be proven beyond all reasonable doubt and Jose boiled over again when Arsenal were trying to sign Chelsea's goalkeeper Petr Cech for £10m in the summer of 2015. Mourinho wasn't interested in the money. He wanted to keep Cech but was overruled by owner Roman Abramovich.

He took his frustration out on Wenger, whom he blamed for unsettling Cech, and immediately hatched a plan to try to turn a straightforward cash sale into a swap deal in a bid to prise away, or at the very least unsettle, a couple of young Arsenal stars in retaliation.

He told me in an email: 'Mister Wenger wants Cech and he thinks about money...he is wrong!!! What I want is to f*** him...Want Cech? OK, I want (Theo) Walcott or (Alex) Oxlade-Chamberlain!!! Want a top goalkeeper? OK, I want a young player, s*** with you but I can make him top.'

Mourinho did not want to sell Petr Cech (left) to Arsenal, but the goalkeeper made the move

The inference was clear. He could make Oxlade-Chamberlain and Walcott top, top stars and succeed where Wenger had failed.

On this occasion the Frenchman had the last laugh for once, landing Cech without sacrificing any of his players and then seeing Mourinho sacked by Christmas 2015.

Almost two decades at one club is an incredible achievement, something Mourinho craves but can never seem to achieve.

For all his stability and security, Wenger has never matched Jose's array of successes — yet in the final analysis, Mourinho puts silverware first and security second.

Extracted from JOSE MOURINHO: UP CLOSE AND PERSONAL by Robert Beasley, published by Michael O'Mara on September 29 at £16.99. ©Robert Beasley 2016.