In train wreck, old Sophocles? (9)
I believe the answer is:
tragedian
'sophocles?' is the definition.
(Sophocles wrote tragedies)
'in train wreck old' is the wordplay.
'in' is an insertion indicator.
'wreck' indicates an anagram.
'old' becomes 'aged' (similar in meaning).
'train' is an anagram of 'trian'.
'trian' enclosing 'aged' is 'TRAGEDIAN'.
(Other definitions for tragedian that I've seen before include "actor in Macbeth?" , "Egad, I rant about actor in sad drama" , "Egad, I rant about dramatic actor" , "Dramatist" , "A great din (anag) - actor" .)