European run with Coe on the outside (4)
I believe the answer is:
serb
'european' is the definition.
(person from Serbia)
'run with coe on the outside' is the wordplay.
'run with' becomes 'r' (cricket abbreviation. I am not sure about the 'with' bit.).
'coe' becomes 'seb' (athlete and politician Seb Coe).
'on the outside' means one lot of letters goes inside another.
'r' placed into 'seb' is 'SERB'.
(Other definitions for serb that I've seen before include "One from Belgrade" , "A European national" , "Someone from Belgrade?" , "Eg, native of Belgrade" , "Balkan native" .)