In an inferior position (5)
I believe the answer is:
under
'in an inferior' is the definition.
'under' can be an answer for 'inferior' (I've seen this before). I'm not certain of the 'in an' bit.
I can't explain the remainder of the clue.
Can you help me to learn more?
(Other definitions for under that I've seen before include "Less than" , "One prepared to take over from leading actor" , "Lower than" , "Subject to the authority of" , "Covered" .)