The rookie defenseman appeared to undercut Dorsett, upending him in a play that infuriated Dorsett's teammates and resulted in a clipping penalty.
"I mean, in my opinion, that's real dangerous," Vigneault said. "Any time you're going for knees, you're looking at career-ending injuries here."
Dorsett appeared to be OK after the hit, but that didn't seem to placate Vigneault.
"That was borderline very, very dangerous."
"It hurt at the time," said the 25-year-old winger, who scored twice as New York won its third straight, "but it's fine." Hagelin doesn't anticipate it being a problem.