[s-cars] Clutch stopped working

[Theodore Chen]

On a freeway on-ramp, I tried to shift 2-3 at full throttle, and found the clutch was gone.  I managed to get it into 3rd and limped it back home, with a lot of creative driving to avoid having to stop or take it out of 3rd.  Depressing the clutch did seem to disengage the engine, so it's not 100% gone but it's mostly non-functional.  Also, if I remember right, the clutch also slipped when I tested it with heavy throttle.

There is some resistance from the clutch pedal, but not much.  It comes back up every time I press it.  I don't recall whether there's a spring to help pedal return.

II pumped the clutch pedal but no change in behavior.  The brake fluid reservoir (which I understand is shared with the clutch) is full, and the brakes work fine.

Any idea what this might be?  Blown clutch slave cylinder?  Clutch and transmission are stock, with 174k miles.

-Teddy