Left scratching my head. Clutch issues

[BimBim2oo2]

Make a long story short....

My wheel decided to have a date with a curb last week. My car has been pretty much sitting for over a week. It was on jack stands at my work for three days then I was able to get it home on a spare wheel where it has been sitting til today.

I went and picked my wheel up today. I go to start my car and the clutch pedal goes straight to the floor with no resistance and does not spring back. I look over all the obvious and cant find anything. The resavoir was full and I saw no leaks. I then decide to try and bleed the system thinking maybe air got in there somehow. Well sure enough thats what it was. I did a 1/2 ass bleed job with a oil pump and some hose on the nipple of the slave forcing the air up.

My question now is what would cause air to get into the system? When I drove the car home a few days ago everything was fine (drove it home Friday). It has been parked on a level surface. Im just a little lost right now on what exactly I should be looking at. Like I said there were no leaks and the resevoir was full.

Any ideas?