As soon as the Premier League's fixtures came out a week ago, the headlines were up on Portugal's sports media outlets - "Mourinho visits Villas-Boas on game day 6", as Mais Futebol had it, being typical of the focus on Chelsea's visit to Tottenham on the last weekend of September.
Concentrating on two of the Liga's most prestigious alumni meeting in the world's most high-profile domestic competition is to be expected in Portugal, but there is a sense outside the country - and especially in England - that their could be something in this. This feeling is particularly keen in a post-Sir Alex Ferguson landscape, with new rivalries and narratives waiting to be born.
Both men have played down the encounter; Mourinho was careful to group Villas-Boas with Brendan Rodgers and Steve Clarke as former colleagues, rather than play up the Porto connection, in his opening press conference after returning to Stamford Bridge. Villas-Boas, meanwhile, told Monday's edition of Portuguese daily O Jogo in an extensive interview about a recent conversation he had with his goalkeeper Hugo Lloris on how managers are bigger stars than they should be.
"In my opinion," he said, "in football today, there's too much focus on head coaches, especially in teams where you have important, decisive players, but ones without the same profile as Ronaldo or Messi." The last part of that assessment leaves little to the imagination. Mourinho rarely ventures into such brutal self-depreciation.
The question now is whether two contrasting personalities will continue to ignore each other, or if direct confrontation will force some sort of clash, particularly if Chelsea and Spurs do indeed turn out to be genuine competitors next season. The initial schism was borne of a fundamental difference in outlook, and a resulting lack of empathy. Mourinho simply couldn't fathom why Villas-Boas would want to turn his back on Inter in October 2010 to take the head coach's job at Academica. He had given AVB extra responsibility in Milan compared with what the tyro had undertaken when the pair were at Chelsea together - not to mention the massive pay cut that the younger man accepted to return to Portugal.
Villas-Boas's gamble paid off, providing a quick route to the Porto job, where he made the basis of his reputation and more. It was at the Dragão that he showed he had a few things in common with Mourinho, however much both men may deny this is the case. He built a side that positively dripped with his own personality; forthright, dynamic and impetuous, in his case. Villas-Boas also mirrored Mourinho's capacity to be a very bad loser. On the first occasion that Porto dropped points under AVB, in October 2011 at Guimarães, he went on a paranoid - and incorrect - rant at the referee after the game, drawing focus from his team's errors. Ring any bells?
Of course, Villas-Boas has changed since then, marked and matured by his own experience in the top job at Chelsea by his own admission. As this excellent look at Mourinho's return by Andi Thomas recognises, he has come back to a Premier League where potential antagonisms are thin on the ground. "I've no idea," Villas-Boas responded when asked by O Jogo who could "dispute space in the media with Mourinho". As much as both men are seemingly trying to avoid it, the answer could be closer to home than they think. These two apparent opposites with more common ground than they think provide potential for a slow-burning, but fascinating rivalry.
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