In all Melrose ran in five tries, four of them in a powerful first-half performance that had the Hawick defence stretched.
For Hawick, who had harboured slender hopes of obtaining at least one championship point, the result means that Premiership survival will depend on winning the play-off match, likely to be in May.
Hawick’s chances were quickly reduced to nothing after a succession of game-ending injuries that required them to empty their bench by early in the second half, and two further departures left them with only 13 players for the final ten minutes.
Tries by Ruairdh Knott, Ian Moody, George Taylor and Fraser Thomson and seven points from the boot of Jason Baggott gave Melrose a 27-0 interval lead.
Melrose could add only one further score, a converted try for Baggott, matched by Ali Weir’s conversion and try for Hawick.