Practically of an equally high standard (2,4,2)
I believe the answer is:
as good as
'practically' is the definition.
(I've seen this before)
'of an equally high standard' is the wordplay.
I cannot really see how this works, but
'of' could be 'o' and 'o' is present in the answer.
'an' could be 'a' and 'a' is found within the answer.
'equally' could be 'as' (synonyms) and 'as' is found within the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for as good as that I've seen before include "Virtually" , "'Enough is . . . . . . . . a feast' (2.4.2)" , "Matching" , "of the same standard" , "Very nearly" .)