A girl in distress sought by Lohengrin (5)

I believe the answer is:

grail

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'sought by lohengrin' is the definition.
The definition suggests a singular noun which matches the answer.

'a girl in distress' is the wordplay.
'in distress' indicates an anagram.
'a'+'girl'='agirl'
'agirl' is an anagram of 'GRAIL'.

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(Other definitions for grail that I've seen before include "Holy object of search" , "Cherished ambition (sought by the Knights of the Round Table)" , "Last Supper cup" , "Arthurian knights' quest" , "Holy vessel used at the Last Supper" .)

I've seen this clue in The Globe and Mail.

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