Bet made by sports pro in New York (6)
I believe the answer is:
yankee
I believe this clue is a double definition.
'bet' is the first definition.
(I've seen this before)
'sports pro in new york' is the second definition.
(New York Yankees baseball team)
'made by' acts as a link.
(Other definitions for yankee that I've seen before include "N. American" , "A Connecticut - in King Arthur's Court (Twain)" , "1942 film with James Cagney" , "baseballer?" , "- - Doodle, song" .)