Tramp’s clues, ultimately knocked back: awful feeling (11)
I believe the answer is:
sympathetic
'feeling' is the definition.
(thesaurus)
'tramp's clues ultimately knocked back awful' is the wordplay.
'tramp's' becomes 'my' (I can't justify this - if you can you should believe this answer much more).
'ultimately' says to take the final letters.
'knocked back' is a reversal indicator.
'awful' becomes 'pathetic' (both can mean of poor quality).
The final letter of 'clues' is 's'.
'my'+'s'='mys'
'mys' in reverse letter order is 'sym'.
'sym'+'pathetic'='SYMPATHETIC'
(Other definitions for sympathetic that I've seen before include "Compassionate" , "Showing fellow-feeling" , "Understanding" , "Solicitous" , "Likable" .)