As commanded by tennis umpires or judges? (5,2,5)

'judges?' is the definition.
I know nothing about this answer so I cannot judge whether this works.

'as commanded by tennis umpires or' is the wordplay.
I cannot quite understand how this works, but
'as' could be 'in' (I've seen this in other clues) and 'in' is found within the answer.
'tennis' could be 'court' (court tennis is a kind of tennis) and 'court' is located in the answer.
'or' is found in the answer.
The remaining letters 'der' 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?