Baseball player put champions in first place (8)
I believe the answer is:
backstop
'baseball player' is the definition.
(I've seen this before)
'champions in first place' is the wordplay.
'champions' becomes 'backs' (as verb - supports).
'in first place' becomes 'top' (of a list or table).
'backs'+'top'='BACKSTOP'
'put' acts as a link.
(Other definitions for backstop that I've seen before include "baseball catcher" , "baseball player" .)