'Tabloid Kelvin' is done for (4)
I believe the answer is:
sunk
'done for' is the definition.
('sunk' can be a synonym of 'done for')
'tabloid kelvin' is the wordplay.
'tabloid' becomes 'sun' (The Sun, UK newspaper).
'kelvin' becomes 'k' ('K' can be a synonym of 'kelvin').
'sun'+'k'='SUNK'
'is' acts as a link.
(Other definitions for sunk that I've seen before include "Sent to bed" , "Doomed - bored" , "(Has) disappeared beneath the waves" , "Submerged" , "suffered decline" .)