Betting on a new connection (4)
I believe the answer is:
span
'connection' is the definition.
(I've seen this in another clue)
'betting on a new' is the wordplay.
'betting' becomes 'sp'.
'on' means one lot of letters go next to another.
'new' becomes 'n' (common abbreviation eg NT for New Testament).
'sp'+'a'+'n'='SPAN'
(Other definitions for span that I've seen before include "Bridge - rotated" , "The total spread" , "Complete duration" , "Stretch < fresh" , "Extent of 20" .)