Sailors said to follow a classical hero (4)
I believe the answer is:
ajax
'a classical hero' is the definition.
(hero in Greek myth)
'sailors said to follow' is the wordplay.
'sailors' becomes 'jacks' (jack can informally mean a sailor).
'said' shows a homophone (sound like).
'to' means one lot of letters go next to another (I've seen this in other clues).
'follow' becomes 'a' (I can't justify this - if you can you should believe this answer much more).
'jacks' sounds like 'jax'.
'jax' put after 'a' is 'AJAX'.
(Other definitions for ajax that I've seen before include "Amsterdam football team" , "It's quite often seen in loo" , "Legendary warrior" , "Son of Telamon, hero of Trojan War" , "classic war hero" .)