Hurry up, or set point lost (4,2,2)
I believe the answer is:
step on it
'hurry up' is the definition.
'set point lost' is the wordplay.
'lost' indicates an anagram.
'set'+'point'='setpoint'
'setpoint' anagrammed gives 'STEP ON IT'.
'or' is the link.
(Other definitions for step on it that I've seen before include "Get a move on!" , "Move quickly" , "Informally, hurry or drive faster" , "Be quick" , "Hurry! - set point (anag)" .)