A change of rod (6)
I believe the answer is:
switch
I believe this clue is a double definition.
'a change' is the first definition.
(switch is a kind of change)
'rod?' is the second definition.
(I've seen this before)
'of' is the link.
(Other definitions for switch that I've seen before include "birch" , "Device for completing or breaking an electrical circuit" , "that turns on the power" , "Shift" , "Change; false hair" .)