I can't get the chuck open to remove fillips head screw driver insert

There is a fillips head driver insert stuck in the (closed) chuck. I can, with force, break the chuck loose going either way, but it will only rotate a very little amount freely and it stops again. It is tightly clamped on the driver insert--which is jammed in as far as it will go, leaving only a 1/4" of the tip sticking out the chuck. Is the clutch locked up/ruined from trying to open it? Would a replacement clutch assembly be the best/quickest fix?