Toy with cricket side, leading to duck (4)
I believe the answer is:
lego
'toy' is the definition.
(I've seen this before)
'cricket side leading to duck' is the wordplay.
'cricket side' becomes 'leg' (I've seen this before).
'leading to' is a charade indicator (letters next to each other) (some letters go before or lead others).
'duck' becomes 'o'.
'leg'+'o'='LEGO'
'with' acts as a link.
(Other definitions for lego that I've seen before include "Toy with interlocking blocks" , "Small bricks" , "Toy building-bricks" , "Building bricks for children" , "construction kit" .)