Edgy trainer to meet individual at town on the Shannon, shortly, for sporting event (9)

I believe the answer is:

triathlon

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'for sporting event' is the definition.
(I've seen this before)

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

(Other definitions for triathlon that I've seen before include "Multi-disciplined Olympic event since 2000" , "Sporting event" , "Three-event athletic contest" , "Athletic contest in three events" , "Sporting contest comprising swimming, cycling and running" .)

I've seen this clue in The Irish Times.

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