Old team showing its age, getting rusty? (9)

I believe the answer is:

oxidating

'getting rusty?' is the definition.
(oxidate means to rust)

'old team showing its age' is the wordplay.
'old' becomes 'o' (abbreviation).
'team' becomes 'XI' (a football team, from Roman numerals for 11).
'showing its age' becomes 'dating' (if something is dated it shows its age).
'o'+'xi'+'dating'='OXIDATING'

I've seen this clue in The Guardian.

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