Athlete's carpet (6)
I believe the answer is:
runner
This clue is a double definition.
'athlete's' is the first definition.
(type of athlete)
'carpet' is the second definition.
(I know that runner is a type of carpet)
(Other definitions for runner that I've seen before include "Percussion instrument" , "Harrier" , "Roadworthy vehicle" , "Canvas shoe with a rubber sole" , "Horse in a race; shoot" .)