Here the reason why Cristiano Ronaldo isn't going to leave Real Madrid, despite his recent falling out with the club: €1,000,000,000.

That's the value of the buyout clause in Ronaldo's contract, according to Spanish media (via the Telegraph).

So if any team wants to jump in and sign the world's best (er, second best) player before 2015, they'd have to pony up 10 figures.

That ain't happening.

PSG, Manchester City, Anzhi Makalaka, and Chelsea are all owned by billionaires who've shelled out hundreds of millions of dollars for players.

But €1 billion is an entirely different ballpark. The current world record for a soccer transfer is $93 million, which Madrid spent to pry Ronaldo from Manchester United in 2009.

The only way Ronaldo leaves Madrid is if this buyout clause is way less than the reported value, or if Madrid is willing to negotiate a smaller buyout settlement.

So if you're a fan of one of these uber-rich clubs hoping to land Ronaldo, don't get your hopes up.