Axle Trouble, Broken axle right after replacement

[Zanderflex]

So I have a 1994 with ~200k miles on it and a few weeks ago the spider assembly on one of my axles went bad and resulted in a whole load of play between the wheel/hub and the rest of the axle. So I ordered a new axle, put it in, then everything was fine.

However today I hear a light clunking noise on my way home from work, I lift up the car and lo and behold the same play in the axle as before!! Now I know that I could have gotten really unlucky and received a bad axle, but does anyone know if its possible something else is broken that is causing only the spider assembly to break on only one of my axles?