Ultimately, cap super headgear for cricketer (4,6)
I believe the answer is:
pace bowler
'cricketer' is the definition.
(I've seen this before)
'ultimately cap super headgear' is the wordplay.
'ultimately' indicates one should take the final letters.
'super' becomes 'ace' (synonyms).
'headgear' becomes 'bowler' (bowler is a kind of headgear).
The last letter of 'cap' is 'p'.
'p'+'ace'+'bowler'='PACE BOWLER'
'for' acts as a link.
(Other definitions for pace bowler that I've seen before include "One quickly delivers" , "Cricketer" , "He's quick" .)