Manual Transmission - Need Help

So i have a t56 and something in the hydraulics decided to break. What happened was all of a sudden when i went to shift from 3rd to 4th i thought i missed my shift. However it turns out i lost something in the hydraulics. I made it back to my parking lot without using a my clutch, useless at this point, and i looked at the resivoir and the fluid did not drop at all, it was black though. This led me to think (hope) my master went in it and i replaced it and i tried bleeding the new one and with the tips on here i could not get any pressure to build up at all. So my question is have you guys heard of a slave cylinder going completely out in one shift without any noises?

Thanks

Mine did about a week ago. There's a chance it was your o ring, check the stainless line going into your bellhousing for fluid. Otherwise, it was probably your slave. Mine got caught on my shift fingers somehow... tore apart the slave, bearings fell out of the slave into my starter and ruined it too lol. Your clutch may or may not have been ruined by the fluid getting on it, mine was about to go anyway so I'm ordering a replacement today.
That's what happened to me anyway.