Intense ones face off by English river (9)

I believe the answer is:

tennessee

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'river' is the definition.
(I know that Tennessee is a river)

I cannot understand how the rest of the clue works.

(Other definitions for tennessee that I've seen before include "playwright's assumed first name" , "State of south-east US" , "Southern US state" , "16th US state" , "Name of US dramatist" .)

I've seen this clue in The Daily Express.

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