For achilles to rupture, something has to occur. Usually you are impactd from behind or it gives out when you push off to jump or sprint. There is no guarantee that this occurs on a different pitch at a different club. The achilles of Senderos as a Newcastle player exists completely seperatly from the achilles of Senderos as an Arsenal player.
Does it bollocks. If a body part is susceptible to injury, it's susceptible to injury wherever. Direct trauma might well be a factor, but chances are this was coming for a while. Wear and tear or persistent inflamation being likely contributors if so. I've ruptered mine twice by the way, so this isn't arguing for the sake of it, for once.