Like a wild horse, without provisos (9)
I believe the answer is:
riderless
'without provisos' is the definition.
('proviso' can be 'rider' (I've seen this before) so maybe 'without provisos' can be ''riderless')
'like a wild horse' is the wordplay.
I cannot really see how this works, but
'horse' could be 'ride' (animal that can be ridden) and 'ride' is present in the answer.
The remaining letters 'rless' is a valid word which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for riderless that I've seen before include "like liberty horses" , "Without addendum" , "without one taking seat" , "Some Grand National runners may become so" , "unqualified?" .)