Alf may be out to take in the big match (5)
I believe the answer is:
final
'the big match' is the definition.
(I've seen this before)
'alf may be out to take' is the wordplay.
'may be' is an anagram indicator.
'out' means one lot of letters goes inside another.
'to take' becomes 'in' (I can't justify this - if you can you should believe this answer much more).
'alf' is an anagram of 'fal'.
'fal' placed around 'in' is 'FINAL'.
'in' acts as a link.
Can you help me to learn more?
(Other definitions for final that I've seen before include "Last match in a competition" , "Concluding" , "Last in a series of games or contests" , "Like one's journey to cemetery" , "Conclusive" .)