Knocked over and split, sadly (5)
I believe the answer is:
spilt
'knocked over' is the definition.
(I've seen this in another clue)
'split sadly' is the wordplay.
'sadly' is an anagram indicator.
'split' with letters rearranged gives 'SPILT'.
'and' is the link.
(Other definitions for spilt that I've seen before include "Overflowed" , "Poured forth" , "(Liquid) slopped" , "Slopped over the edge" , "(Of liquid) dropped" .)