Football team rose and improved field? (7)

I believe the answer is:

manured

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'improved field?' is the definition.
Although both the answer and definition are past participle verbs, I cannot see how one could define the other.

'football team rose' is the wordplay.
'football team' becomes 'man u' (short for Manchester United).
'rose' becomes 'red' (shade of red).
'manu'+'red'='MANURED'

'and' acts as a link.

Can you help me to learn more?

(Another definition for manured that I've seen is " mucky".)

I've seen this clue in The Telegraph.

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