Fine time standing up a box (7,4)
I believe the answer is:
penalty area
'box' is the definition.
(I've seen this before)
'fine time standing up a' is the wordplay.
'fine' becomes 'penalty' (I've seen this before**).
'time' becomes 'era' (I've seen this before).
'standing up' says the letters should be written backwards (in a down clue up is reverse order).
'era' in reverse letter order is 'are'.
'penalty'+'are'+'a'='PENALTY AREA'
(Other definitions for penalty area that I've seen before include "Region in front of a goalkeeper" , "The 18-yard box" , "Football's box" , "It's adjacent to goal" .)