Telephone to say the arena has been erected (4,2)
I believe the answer is:
ring up
'telephone' is the definition.
(I've seen this before)
'the arena has been erected' is the wordplay.
I cannot quite understand how this works, but
'arena' could be 'ring' (I've seen this in other clues) and 'ring' is located in the answer.
'erected' could be 'up' and 'up' is found in the answer.
No letters remain.
This may be the basis of the clue (or it may be nonsense).
'to say' is the link.
Can you help me to learn more?
(Other definitions for ring up that I've seen before include "Contact by phone" , "Try to contact" , "Telephone someone or record on cash register" .)