Leave stranded and in the red? (6)
I believe the answer is:
maroon
This clue is a double definition.
'leave stranded' is the first definition.
(synonyms)
'the red?' is the second definition.
(thesaurus)
'and in' acts as a link.
(Other definitions for maroon that I've seen before include "Brownish-crimson - abandon ashore" , "Brownish crimson" , "castaway?" , "Isolate uncomfortably" , "Could be a warning signal" .)