Hit the XO? (6,3)
I believe the answer is:
number one
I believe this clue is a double definition.
'hit' is the first definition.
(I've seen this before)
'the xo?' is the second definition.
(both can refer to an executive officer)
(Other definitions for number one that I've seen before include "Cut" , "the most important person" , "top-selling record" , "Chief - First Lieutenant - myself" , "top of the pops" .)