United made it three wins in a row and five games unbeaten with a comfortable victory over Burnley at the weekend.
Newcastle haven't conceded a goal in their last five matches and rarely looked like doing so here, although Nick Pope made a fine save against his former club in the opening exchanges before the Magpies began to assert their authority in the fixture.
Miguel Almirón's great goal - his second in two league games - gave Eddie Howe's side the lead, before Alexander Isak wrapped up the win from the penalty spot in the second period.
He has now scored in the last three games - and will look to extend that run when Newcastle welcome Paris Saint-Germain to Tyneside on Wednesday night for their first Champions League home game in 20 years.
Club photographer Serena Taylor, assisted by Michelle Mercer, brought nufc.co.uk this gallery.