Where distance takes its toll, ultimately (2,3,4,3)
I believe the answer is:
in the long run
'ultimately' is the definition.
(thesaurus)
'where distance takes its toll' is the wordplay.
I cannot really see how this works, but
'distance' could be 'in' and 'in' is located in the answer.
This may be the basis of clue (or it may be nonsense).
(Other definitions for in the long run that I've seen before include "marathon effort" , "some time later" , "participating in marathon" , "qualified for a marathon?" , "Where steeplechasers go" .)