The rotten fellow tripped up! (6)

I believe the answer is:

fouled

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'up' is the definition.
Both the answer and definition are adjectives. Perhaps they are linked in a way I don't understand?

'the rotten fellow tripped' is the wordplay.
I cannot quite understand how this works, but
'fellow' could be 'ed' (short for Edward) and 'ed' is found within the answer.
The remaining letters 'foul' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...

Can you help me to learn more?

(Another definition for fouled that I've seen is " Soiled or broke the rules of the game".)

I've seen this clue in the Evening Standard.

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