Start with metal not available (4,3)
I believe the answer is:
lead off
'start' is the definition.
(I know that start is a more specific form of lead off)
'with metal not available' is the wordplay.
'with' is a charade indicator (letters next to each other).
'metal' becomes 'lead' (lead is a kind of metal).
'not available' becomes 'off' (eg the power might be off).
'lead' put next to 'off' is 'LEAD-OFF'.
(Other definitions for lead off that I've seen before include "Begin, start" , "Initiate an action" , "Begin the dance" , "Make a start" .)