Ginger is out of practice (5)

I believe the answer is:

rusty

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'out of practice' is the definition.
(synonyms)

I cannot understand how the rest of the clue works.

(Other definitions for rusty that I've seen before include "showing sign of inactivity?" , "Behind the times" , "Affected by corrosion - out of practice" , "(Of iron) affected by damp" , "Having a reddish-orange oxide coating" .)

I've seen this clue in The Sun.

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