Bring on popular dog (5)
I believe the answer is:
incur
'bring on' is the definition.
(thesaurus)
'popular dog' is the wordplay.
'popular' becomes 'in'.
'dog' becomes 'cur' (I've seen this before).
'in'+'cur'='INCUR'
(Other definitions for incur that I've seen before include "Become subject to (eg, taxes)" , "contract" , "Become liable to (something) through one's actions" , "Runic (anag.)" , "Take on (obligation)" .)