Couple I ran into knocked over (4)
I believe the answer is:
item
'couple' is the definition.
(I've seen this before)
'i ran into knocked over' is the wordplay.
'ran into' becomes 'met'.
'knocked over' is a reversal indicator.
'met' in reverse letter order is 'tem'.
'i'+'tem'='ITEM'
(Other definitions for item that I've seen before include "Unit or distinct part" , "Article, object" , "Loving couple" , "Whole individual unit" , "Detail - entry" .)