You have to understand McDermott to get the anger. Ingram is a kid who scrapped, and worked, and who was respectful, and who came from nothing and never gave up. McD is sort of similar - high school wrestler, undersized, all hustle, hardworking, focused, etc. @GunnerBill is probably dead on with the Keon suggestion. Coleman is a non malevolent bonehead who is immature and plays too many video games and has no attention to detail. That goof sticking while Ingram walks out the door for nothing has got to infuriate McD.
What most people also don't understand is that guys like Marino and Tim Graham hear stuff they can't report. So when you get these little nuggets from each of them . . . treat it as a little bit of subtly-identified smoke.