Reserve goalie an expert at balancing acts? (10)
I believe the answer is:
bookkeeper
'an expert at balancing acts?' is the definition.
(a bookkeeper balances the books)
'reserve goalie' is the wordplay.
'reserve' becomes 'book' (to book something is to reserve it).
'goalie' becomes 'keeper' (I've seen this before).
'book'+'keeper'='BOOKKEEPER'
(Other definitions for bookkeeper that I've seen before include "Accounts official" , "who works to maintain balance" , "person responsible for financial oversight" , "Business occupation" , "accountant" .)