Regards as champions, without exception (3,3,4)
I believe the answer is:
all the best
'regards as champions' is the definition.
I can't tell whether this defines the answer.
'without exception' is the wordplay.
I cannot quite understand how this works, but
'without exception' could be 'all' (I've seen this in another clue) and 'all' is present in the answer.
The remaining letters 'thebest' 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 all the best that I've seen before include "flower, every bit of it?" , "Good health!" , "needing good luck!" , "everyone in the top echelon" , "A greeting" .)