Spectator originally keen on following race meets (4,4)
I believe the answer is:
runs into
'meets' is the definition.
(I've seen this in another clue)
'spectator originally keen on following race' is the wordplay.
'originally' indicates taking the first letters.
'keen on' becomes 'into' (I've seen this before).
'following' is a charade indicator (letters next to each other).
'race' becomes 'run' (synonyms).
The initial letter of 'spectator' is 's'.
's'+'into'='sinto'
'sinto' put after 'run' is 'RUNS INTO'.
(Other definitions for runs into that I've seen before include "Meets - collides" , "contacts - with 17a" .)