Stemming from name of John Marston, protagonist of the video game
Red Dead Redemption, in which Marston is capable of inducing and inflicting pain and sorrow with his guns, brash attitude, and defined sense of vengeance.
Getting "marstonized" is another way of saying "merc'd/mercked/merked", whilst competing at an activity with someone else.
Being badly beaten at a game or
competition; being beat in a fight; being
embarrassed in a competitive environment.
(also: marstonization)