Sign "Love from the guys" (4)
I believe the answer is:
omen
'sign' is the definition.
(omen is a kind of sign)
'love from the guys' is the wordplay.
'love' becomes 'o' (love means zero in tennis).
'from' means one lot of letters go next to another.
'the guys' becomes 'men'.
'o'+'men'='OMEN'
(Other definitions for omen that I've seen before include "Warning token" , "Portent of things to come" , "Sign of something about to happen" , "writing on the wall" , "premonition" .)