Sank red in error, becomes gloomy (7)

I believe the answer is:

darkens

'becomes gloomy' is the definition.
(I've seen this before)

'sank red in error' is the wordplay.
'in error' is an anagram indicator.
'sank'+'red'='sankred'
'sankred' with letters rearranged gives 'DARKENS'.

(Other definitions for darkens that I've seen before include "becomes gloomy" , "Gets black" .)

I've seen this clue in the Sydney Morning Herald.

Want a hint initially instead of a full solution? Install my app