Run pub in transport centre, say? Nonsense (7)
I believe the answer is:
rhubarb
'nonsense' is the definition.
(rhubarb can mean nonsense or rubbish)
'run pub in transport' is the wordplay.
'run' becomes 'r' (cricket abbreviation).
'pub' becomes 'bar' (both are drinking establishments).
'in' is an insertion indicator.
'transport' becomes 'hub' (I can't explain this - if you can you should give a lot more credence to this answer).
'bar' inserted inside 'hub' is 'hubarb'.
'r'+'hubarb'='RHUBARB'
'centre say?' is the link.
This may not be right. Some or all of it may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for rhubarb that I've seen before include "Garden plants with fleshy stalks or slang nonsense" , "Indistinct stage chattering noise by actors" , "Plant, its stalk eaten" , "Crowd word on stage" , "Reddish leafstalks cooked and eaten as fruit" .)