Winning cheers up soldiers obstructing corruption (10)
I believe the answer is:
attainment
'winning' is the definition.
(thesaurus)
'soldiers obstructing corruption' is the wordplay.
'soldiers' becomes 'men' (men can mean a group of soldiers).
'obstructing' is an insertion indicator (inserted letters interrupt or obstruct the word).
'corruption' becomes 'attaint' (I am not sure about this - if you are sure you should believe this answer much more).
'men' put inside 'attaint' is 'ATTAINMENT'.
'cheers up' is the link.
I am not very happy about this link. Some or all of it may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for attainment that I've seen before include "Act of achieving something" , "Feat achieved" , "Laudable exploit" , "Realisation" , "The achievement (of a goal)" .)