Didn't see this posted or discussed anywhere. Saw this article on Yahoo! regarding Arod crossing over the pitchers mound while retreating to first from third base. It appears that he crossed over the pitchers mound and stepped on the rubber. Oakland pitcher Dallas Braden was having none of it.
Arod certainly seems to know very little about unwritten baseball rules and etiquette. If I'm not mistaken he was in some sort of similar situation last year while running down the baseline.
Here a couple notable quotes from him
"He should probably take a note from his captain over there and realize you don't cross the pitcher's mound in between an inning or during the game. I was just dumbfounded that he would let that slip his mind — being someone of such status."
"I don't care if I'm Cy Young or the 25th man on the roster, if I've got the ball in my hand and I'm on that mound, that's my mound ... He ran across the pitcher's mound foot on my rubber. No, not happening. We're not the door mat anymore."