Dortmund took the lead after a fierce first half in which Nick Pope produced a world-class double save to deny Donyell Malen and Niclas Fullkrug.
Felix Nmecha scored the eventual game-winning goal from inside the box, giving Newcastle its first deficit in the Champions League this season.
The goal demonstrated the visitors’ strength in transition during the first forty-five minutes in particular, as Nmecha gave his team the lead ten seconds after Nico Schlotterbeck tackled Anthony Gordon in the Dortmund half.
It was Nmecha’s first goal for Dortmund since his move from Wolfsburg in the summer. Newcastle were also linked with a move for the 23-year-old, with Howe confirming afterwards: “He’s a player we looked at and we really liked but he went to Borussia Dortmund.”
Newcastle ultimately went on to sign Tonali instead as their main midfield addition instead, though Howe was quick to remind reporters in his post-match press conference: “It’s never as simple as that.”