In which to do as well as the opposition? (5)
I believe the answer is:
match
This clue could be a double definition.
'in which to do as well' is the first definition.
Although both the answer and definition are singular nouns, I cannot see how they can define each other.
'the opposition?' is the second definition.
The definition and answer can be both groups as well as being singular nouns.
Perhaps you can see a link between them that I don't see?
'as' acts as a link.
Can you help me to learn more?
(Other definitions for match that I've seen before include "one's struck" , "Lighter; contest" , "Partnership" , "An exact duplicate or a contest between two" , "Correspondence" .)