Star more annoyed being in last place (8)
I believe the answer is:
rearmost
'in last place' is the definition.
'star more annoyed' is the wordplay.
'annoyed' indicates an anagram.
'star'+'more'='starmore'
'starmore' with letters rearranged gives 'REARMOST'.
'being' is the link.
(Other definitions for rearmost that I've seen before include "Fully behind" , "Furthest back" , "farthest from the front" , "More rats (anag)" , "last" .)