Gunners behind on table at regular intervals (7)
I believe the answer is:
arsenal
'gunners' is the definition.
(I've seen this before)
'behind on table at regular intervals' is the wordplay.
'behind' becomes 'arse' (both can mean the buttocks).
'at regular intervals' indicates alternate letters.
'on'+'table'='ontable'
The alternating letters of 'ontable' are 'nal'.
'arse'+'nal'='ARSENAL'
(Other definitions for arsenal that I've seen before include "Store of weaponry" , "favoured by some football supporters" , "London premiership football team" , "Football club based at Emirates Stadium" , "Where the guns are and who are The Gunners are" .)