At boxing yes but boxing is no an effective form of fighting by itself against a trained grappler they are toast in 30 seconds every high school wrestling coach in America with some decent size would wipe the floor with these guys
Early UFC proved that wrestling will dominate all martial arts or combat sports.
Of course now, its all included in the art, wrestling, BJJ, submission, etc. And many are dangerous.
But yup, good wrestler vs a boxer, he'd be on the ground and wrapped up in seconds (the boxer)...