Fielder caught several balls in a row (5)
I believe the answer is:
cover
'fielder' is the definition.
(I've seen this before)
'caught several balls in a row' is the wordplay.
'caught' becomes 'c' (cricket abbreviation).
'several balls in a row' becomes 'over' (cricket term).
'c'+'over'='COVER'
(Other definitions for cover that I've seen before include "Mask, hide" , "Extend over (an area)" , "Totally obscure" , "Lid, travel (distance)" , "Protect - insure" .)