Old argument against one out (2,3)
I believe the answer is:
ex con
'against one out' is the definition.
I know nothing about this answer so I can't tell whether this works.
'old argument' is the wordplay.
'old' becomes 'ex' (prefix meaning former or onetime).
'argument' becomes 'con' (con is a kind of argument).
'ex'+'con'='EX-CON'
Can you help me to learn more?
(Other definitions for ex con that I've seen before include "whose time is over?" , "One now unrestrained" , "He was in prison" , "political defector?" , "One now liberated" .)