They lock horns on the pitch, and they lock horns off it too. When it comes to the most important footballers on the planet, the respective boardrooms and sports directives of Barcelona and Real Madrid frequently have the same stellar transfer targets on their shortlists.
The blockbuster move both are believed to be battling to make this summer, is that of France and Juventus star, Paul Pogba, who has continued to grow and impress as a player, forging a reputation as the most coveted young midfielder in Europe, since Manchester United remarkably let him slip through their grasp.
This week there are interesting developments in the manoeuvres of both clubs, as they try to pave the way for the 22-year-old to make what could be the most important decision of his footballing career: A direct choice between heading to the Camp Nou, or the Santiago Bernabéu.
Of course, the Spanish press are having a field day working out the reasons why Pogba is more likely to choose one or the other, battling for headlines as much as the two clubs are fighting to land the signature of the player they both covet so much.
Starting the week with their take on the ambitions of Real Madrid to secure the services of Pogba, Madrid based Marca points towards the influence of French legend Zinedine Zidane, who has been observed having talks with the Juventus player, whilst on international duty with his country.
Marca also quotes an interview Zidane had with Canal Plus France, in which the 42-year-old Real Madrid Castilla manager acknowledged: "When we're talking about Pogba, it's logical that Real Madrid are interested in him. He has great potential and margin still to improve further. He's young and his future is both promising and exciting."
The iconic and legendary stature of Zidane, both for Real Madrid and France, leads Marca to believe that Pogba will be impressed at having such an important figure take a personal interest in paving the way for a move to the Bernabéu.
In contrast, Catalan outlet Mundo Deportivo believes Real Madrid have actually harmed their chances of landing Pogba, rather than helping them, by letting Zidane speak directly to the player. They claim that the Italian super-agent who represents the young Frenchman, Mino Raiola, is far from impressed.
Mundo Deportivo has suggested that Zidane attempting to turn the head of Pogba towards the Bernabéu, without first going through Raiola, has angered the agent, who they quote as responding: "We don't want to go to a club like Madrid, who use players like towels and then throw them away."
In addition, Mundo Deportivo also suggests Barcelona have an offer which Pogba would prefer. Namely, to stay with Juventus for the first half of next season, then make a switch to the Camp Nou once their FIFA transfer ban ends in January 2016.
Inevitably, both Barcelona and Real Madrid will be doing everything they can and more, to persuade Pogba that this summer, their respective offers and lures are in his best interests. Even though, according to the Express, Manchester United, Chelsea, Manchester City and Arsenal have all been linked, none are likely to stand a chance in this clash of football super-powers.
The supremely talented midfielder will clearly have some tough decisions to make over the coming months, but regardless of the huge wage packet his services will command, or the enormous transfer fee Juventus will undoubtedly receive, it seems inevitable he'll be strutting his stuff in La Liga next season.