European side left with no goals (5)
I believe the answer is:
porto
'european side' is the definition.
(football club FC Porto)
'left with no goals' is the wordplay.
'left' becomes 'port' (left side of a ship - opposite of starboard**).
'with no goals' becomes 'o' (O resembles 0 or zero).
'port'+'o'='PORTO'
(Other definitions for porto that I've seen before include "Portuguese wine city on the Douro" , "City on the Douro estuary" , "City port of Portugal" , "champion of Europe" , "City in NW Portugal (Portuguese spelling)" .)