Sponge used for messy rugs once (8)
I believe the answer is:
scrounge
'sponge' is the definition.
(I've seen this before)
'messy rugs once' is the wordplay.
'messy' indicates an anagram.
'rugs'+'once'='rugsonce'
'rugsonce' anagrammed gives 'SCROUNGE'.
'used for' acts as a link.
(Other definitions for scrounge that I've seen before include "Obtain (something) for free" , "Acquire by begging" , "Cadge, sponge" , "Seek something free from others" , "'Cadge, wheedle (8)'" .)