Someone having a go in German city (5)

I believe the answer is:

trier

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'german city' is the definition.
(Trier is a city in Germany)

I don't understand how the rest of the clue works.

(Other definitions for trier that I've seen before include "one hears" , "Person attempting" , "town in Germany" , "Determined person" , "European city" .)

I've seen this clue in The Times.

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