Fielder from Durham, ultimately, I assume (3-2)
I believe the answer is:
mid-on
'fielder' is the definition.
(I've seen this before)
'durham ultimately i assume' is the wordplay.
'ultimately' suggests the final letters.
'assume' becomes 'don' (I've seen this before).
The final letter of 'durham' is 'm'.
'm'+'i'+'don'='MID-ON'
'from' acts as a link.
(Other definitions for mid-on that I've seen before include "Cricket fielder" , "Leg side fieldsman" , "Fielding position" , "Cricketing position" .)