Miguel Almiron was denied a dream home debut by the woodwork as Newcastle eased their relegation fears by nudging 10-man Huddersfield closer to the Premier League exit.
The Magpies' new record signing saw his cheeky lofted effort come back off the post as he attempted to round off a sumptuous counter-attack, but nevertheless made a significant impression in front of a crowd of 52,174 at St James' Park.
A 2-0 victory was ultimately secured by goals from Salomon Rondon and Ayoze Perez inside the opening seven minutes of the second half with the home side having spent much of the first hammering away at Jonas Lossl's goal as the visitors attempted to re-group following skipper Tommy Smith's 20th-minute dismissal.
Huddersfield had started confidently and it took Newcastle time to work their way into the game, and they were desperately unfortunate not to take the lead after mounting a flowing 12th-minute attack from deep inside their own half.
Fabian Schar, Perez and Sean Longstaff worked their way out of trouble wide on the right for Rondon to lay the ball off to Isaac Hayden, whose first-time pass put Almiron in on goal.
He rode Smith's challenge before lifting the ball audaciously over the advancing Lossl only to see the ball come back of the post with Rondon's follow-up suffering the same fate.
Rondon was denied once again seven minutes later when the keeper parried his close-range effort with the Magpies building a momentum which grew within seconds when Smith was sent off for a studs-up challenge on Almiron.
Lossl had to palm another Almiron effort away as the onslaught continued, but the goalkeeper enjoyed a stroke of good fortune when he allowed the Paraguayan's 30th-minute effort to squirm between his legs and had Chris Lowe to thank for a timely goal-line clearance.
Laurent Depoitre scuffed an effort at Martin Dubravka from Lowe's 32nd-minute cross, but the traffic remained largely one-way and Lossl excelled once again to keep out Perez's strike two minutes before the break before Rondon sent a diving header wide.
He was finally beaten within seconds of the restart when DeAndre Yedlin controlled Florian Lejeune's deep cross and Perez and Hayden helped the ball on to Rondon, who blasted home right-footed on the turn to break the deadlock.
Newcastle extended their lead six minutes later when Perez beat Lossl from Rondon's knock-down to leave the visitors in deep trouble.
The home side were utterly dominant as they looked to kill the game off with Lejeune volleying over acrobatically from Hayden's 69th-minute cross and Perez scuffing wide from Almiron's reverse pass two minutes later.
Lossl produced a remarkable reaction save to turn substitute Kenedy's stinging volley on to the crossbar, and he needed the help of an upright to keep out Longstaff's curling 76th-minute attempt.