As knocked out with a club, perhaps? (5)
I believe the answer is:
divot
'as' is the definition.
Although both the answer and definition are singular nouns, I cannot see how one could define the other.
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for divot that I've seen before include "Clump taken by a golf swing" , "Gouged-out turf" , "Sod" , "Loose piece of turf" , "Piece of turf dug out of the fairway by a golf shot" .)