The victory over Argyle was never as comfortable as the scoreline suggests, and - although Carroll headed just over moments before he scored and then hit the bar at the death - the result was in doubt until the final few minutes of the game.
Having taken the lead through Steven Taylor's header with just six minutes gone, Newcastle inexplicably took their foot of the gas and were very nearly made to pay.
Taylor had already diverted a Jamie Mackie cross against his own post and Karl Duguid punished the home side's carelessness with a 50th-minute equaliser.
Hughton: "There were periods of the game where we made hard work of it.
"For whatever reason, we weren't able to sustain it and of course the longer the game goes without getting that second one, they [Plymouth] are lifted by the occasion and feel they can get something."