Switch racing driver (6)
I believe the answer is:
button
I believe this is a double definition.
'switch' is the first definition.
(I know that button is a type of switch)
'racing driver' is the second definition.
(F1 driver Jenson Button)
(Other definitions for button that I've seen before include "Disc for pushing, fastening" , "Fastener to fit through a hole" , "closer" , "Round fastener" , "Fastener and former F1 driver" .)