Area mainly covered with grass for match (5)
I believe the answer is:
agree
'for match' is the definition.
(as in two tallies agreeing or matching)
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for agree that I've seen before include "Have the same opinion" , "Arrive at a settlement" , "grant" , "Shake on it" , "Hold the same view" .)