Old star trained anew, winning first of Grammies (3,5)

I believe the answer is:

red giant

'old star' is the definition.

I can't explain the rest of the clue.

(Other definitions for red giant that I've seen before include "Huge Communist" , "Large star nearing the end of its life" , "Type of star" , "big star" , "Large, cool bright star" .)

I've seen this clue in The Guardian.

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