Terrible sin, attacking player making a delivery (9)
I believe the answer is:
inswinger
'a delivery' is the definition.
(cricket delivery)
'terrible sin attacking player' is the wordplay.
'terrible' is an anagram indicator.
'attacking player' becomes 'winger' (I've seen this before).
'sin' is an anagram of 'ins'.
'ins'+'winger'='INSWINGER'
'making' is the link.
(Other definitions for inswinger that I've seen before include "moving ball" , "delivery curling through air" , "swerving delivery" , "Swerving ball" , "ball from fast bowler" .)