Poor-quality pitch — what's unusual in that? (6)
I believe the answer is:
shoddy
'poor-quality' is the definition.
(I've seen this before)
'pitch what's unusual in that?' is the wordplay.
'pitch' becomes 'shy' (I've seen this before).
'what's unusual' becomes 'odd' (similar in meaning).
'in that?' means one lot of letters goes inside another.
'shy' going around 'odd' is 'SHODDY'.
(Other definitions for shoddy that I've seen before include "Badly made or done" , "Cheap, of poor quality" , "Cheap and inferior" , "Trashy" , "Of poor quality or workmanship" .)