Row away from river to get fit (4)
I believe the answer is:
ague
'fit' is the definition.
(I've seen this before)
'row away from river' is the wordplay.
I cannot quite understand how this works, but
'away' could be 'a' (abbreviation as used in sports fixtures) and 'a' is present in the answer.
The remaining letters 'gue' is a valid word which might be clued in a way I don't see.
This may be the basis of clue (or it may be nonsense).
'to get' is the link.
Can you help me to learn more?
(Other definitions for ague that I've seen before include "Acute fever; shivering fit" , "Old word for fever" , "Fever (archaic)" , "Sickness" , "Feverish fit" .)