Odds on present will be a ball (6)
I believe the answer is:
sphere
'a ball' is the definition.
(thesaurus)
'odds on present' is the wordplay.
'odds' becomes 'sp' (betting abbreviation for starting price).
'on' says to put letters next to each other.
'present' becomes 'here' ('here' can be similar in meaning to 'present').
'sp'+'here'='SPHERE'
'will be' is the link.
(Other definitions for sphere that I've seen before include "Territory" , "Round solid figure with every point on its surface equidistant from its centre" , "Field; globe" , "Ball shape" , "Social circle" .)