Darren Beadman has been forced into an unaccustomed spectator role for the Derby season after being told he will not be able to ride again until mid-April at the earliest.
Beadman, 46, suffered a broken right cheekbone and head trauma in a fall in a February 17 barrier trial and cannot ride again 'until a minimum six to eight weeks after the injury'.
Doctors have found nerve damage in Beadman's brain - diagnosed as diffuse axonal injury - which has seriously affected his balance.
The Australian left hospital on Thursday night, only to return yesterday morning for the last of his intravenous serum treatments.
Beadman, the rider for the powerful John Moore stable, said: 'At least I got to sleep in my own bed again.
'The serum treatments regenerate brain tissues and hopefully will repair the damage that is affecting my balance, which is still only so-so.
'The doctor says it will come right, but needs time and especially rest. In three weeks, I'll have another MRI scan so they can compare it to the previous one and see what progress I've made.'
Plans to operate on his fractured cheekbone and insert a steel plate have been put on hold, as his doctors are unwilling to put him under anaesthetic in his current condition.
Due to the nature of the problem, Beadman will be unable to leave Hong Kong during his rehabilitation.
'That's going to be hard work. Missing all the good races coming up is tough enough when John has so many great chances in them, especially the Derby,' Beadman said.
'But I can't fly anywhere else because of the air pressure in the plane cabin, so I'll just be stuck here having to watch them from the sidelines.
'I can see me watching a lot of television in the next few weeks. There's nothing I can do but wait.
'With other injuries, you can do things to hurry them along but a brain injury is not something to take lightly and I won't be coming back until I'm really ready.'