Wavered and left a red splash (8)
I believe the answer is:
faltered
'wavered' is the definition.
('falter' can be a synonym of 'waver')
'left a red splash' is the wordplay.
'splash' indicates an anagram (I've seen 'splashed' mean this).
'left'+'a'+'red'='leftared'
'leftared' is an anagram of 'FALTERED'.
'and' is the link.
(Other definitions for faltered that I've seen before include "Hesitated, moved unsteadily" , "Failed" , "was hesitant" .)