Come first in rowing (3)
I believe the answer is:
win
'come first' is the definition.
(as in coming first in a race)
'in rowing' is the wordplay.
'in' says the answer is hidden in the clue.
'WIN' can be found hidden inside 'rowing'.
(Other definitions for win that I've seen before include "Be successful" , "Succeed, conquer" , "Achieve victory" , "Finish in first place" , "Trumph" .)