Hard drink after work? It's child's play (9)
I believe the answer is:
hopscotch
'child's play' is the definition.
(I've seen this before)
'hard drink after work?' is the wordplay.
'hard' becomes 'h' (abbreviation used in pencil classifications).
'drink' becomes 'scotch' (Scotch is an example).
'after' means one lot of letters go next to another.
'work?' becomes 'op' (common abbreviation for 'opus').
'scotch' after 'op' is 'opscotch'.
'h'+'opscotch'='HOPSCOTCH'
'it's' is the link.
(Other definitions for hopscotch that I've seen before include "Children's pavement game" , "Children's game with squares on ground" , "kids jump about in it" , "child's play" , "Jumping game" .)