Just enough juice to operate the central locking, but not enough to turn the engine over.
I can only assume that during the clutch replacement the electrics have been in some way compromised causing the drainage on the battery.
Have recharged it, but after checking it with a meter, it is slowly loosing power. It will probably be flat again by the morning.
Told the garage, and they will look at it on Monday (if I can get it started) !!