Abandons the run, gutted to be behind (6)
I believe the answer is:
astern
'be behind' is the definition.
(at the back or behind of a ship)
I don't understand how the rest of the clue works.
(Other definitions for astern that I've seen before include "Towards the rear of boat" , "Behind the back of a ship" , "Toward the tail of a vessel" , "following behind vessel" , "Towards back of boat" .)