Delectable rugby pack is up to putty (11)
I believe the answer is:
scrumptious
'delectable' is the definition.
(I know that delectable can be written as scrumptious)
'rugby pack is up to putty' is the wordplay.
I cannot really understand how this works, but
'rugby' could be 'ru' and 'ru' is found in the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for scrumptious that I've seen before include "Extremely delicious" , "Delightful" , "Yummy" , "Extremely appetising (colloq.)" , "Toothsome" .)