Obstruction old peasant originally negotiated in athletic event (9)
I believe the answer is:
hindrance
'obstruction' is the definition.
(I know that hindrance is a type of obstruction)
'peasant originally negotiated in athletic event' is the wordplay.
'peasant' becomes 'hind' (archaic term for a peasant).
'originally' suggests taking the first letters.
'in' is an insertion indicator.
'athletic event' becomes 'race' (race is a kind of event. I am not sure about the 'athletic' bit.).
The initial letter of 'negotiated' is 'n'.
'n' inserted into 'race' is 'rance'.
'hind'+'rance'='HINDRANCE'
'old' acts as a link.
I am not very happy about this link. It may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for hindrance that I've seen before include "Block to progress" , "Impediment" , "Obstruction" , "Something inhibiting action" , "barrier" .)