Where Rugby Union needs to go to make it break out is silly (5)
I believe the answer is:
inept
'is silly' is the definition.
(I've seen this before)
I cannot understand how the rest of the clue works.
(Other definitions for inept that I've seen before include "Awkward, showing no skill" , "Not competent" , "Clumsy - silly" , "Unsuitable, clumsy" , "Maladroit" .)