League to raise flag (5,4)

I believe the answer is:

union jack

'flag' is the definition.
(Union Jack is an example)

'league to raise' is the wordplay.
'league' becomes 'union' (I've seen this before).
'to raise' becomes 'jack' (jacking is a kind of raising).
'union'+'jack'='UNION JACK'

(Other definitions for union jack that I've seen before include "UK's standard" , "Colours" , "appears up the pole" , "National flag of United Kingdom" , "The British flag" .)

I've seen this clue in The Telegraph.

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