Successful striker, one making one's mark? (6)
I believe the answer is:
scorer
I believe this clue is a double definition.
'successful striker' is the first definition.
(one who scores goals in football)
'one making one's mark?' is the second definition.
(a person who scores)
(Other definitions for scorer that I've seen before include "Footballer having netted" , "One getting a goal" , "Keeper of the tally" , "Film music arranger" , "Sir, not one without heart as a" .)