"We came to the conclusion that it was better to play together," joke Ariadna Ruiz (Rubí, 2002) and Elena Ruiz (Rubí, 2004). They've almost always played together, but for a brief period they faced each other in the water polo league. It didn't last long. "It's just that we understand each other with a glance. Or not even that. In the pool, sometimes you think you know what a teammate will do, but you don't always get it right. Maybe you ask her for the ball... That doesn't happen with her; you don't have to ask her for it. It's like telepathy. I think about what she'll do, and, indeed, she does it," says the younger sister about the older one. And Ariadna nods in agreement.