A goal by Nolberto Solano eight minutes from time consigned Arsenal to their second successive defeat in the Premiership at St James' Park on Saturday.
Arsène Wenger's side had dominated the first half and only a stunning save by Shay Given stopped Thierry Henry giving them a deserved lead.
However the game changed 12 minutes after the restart when Gilberto fouled Jean-Alain Boumsong and received his second yellow card. Newcastle had already started the second half at pace but the numerical advantage was to tell late in the game.
The visitors failed to clear their lines and a stumbling Alan Shearer fed Solano on the right of the area. The Peruvian buried the chance with a fierce cross-shot.
Much will be made of this result but Arsenal's performance, certainly in the first half, was a cut above that which saw them defeated at Bolton seven days earlier.
However the statistics say they are down to sixth in the Premiership, 17 points behind leaders Chelsea.
Wenger reverted to a more familiar line-up after Wednesday's shuffle for a Champions League tie against Ajax that had meant nothing in terms of qualification.
The returnees were Jens Lehmann, Gilberto, Freddie Ljungberg, Francesc Fabregas, Robin Van Persie and Sol Campbell. Manuel Almunia, Emmanuel Eboue, Seb Larsson, Quincy and Jose Antonio Reyes made way; although the Spanish striker had picked up a thigh injury against the Amsterdam side.
Perhaps the most interesting decisions concerned those who stayed in the side. Alexander Hleb, whose hour against Ajax was his first action for nine weeks, moved from central midfield to the left and, with Pascal Cygan (groin) injured, Wenger retained Lauren at left back. Kolo Toure covered the Cameroonian at right back with Philippe Senderos slotting in at centre half.
The start was slow with neither side imposing themselves on the proceedings. Arsenal had greater possession but Newcastle had the better of the rare half-chances.
Gradually the visitors cranked up the pressure. In the 15th minute, Gilberto's goalbound header from Van Persie's corner was cleared back to the Brazilian. He let fly from 10 yards and the ball hit Newcastle defender Titus Bramble on the hand. Referee Dermot Gallagher waved play on.
Hleb was showing few signs of rust. His tricks were causing havoc on the left and one memorable pass sent Henry clear on the right but the Frenchman's cross came to nothing.
The next chance that came Henry's way should have been converted. The cross from Fabregas on the right was perfect and the Arsenal captain made fierce sidefoot contact at the near post. They had done nothing wrong, it was just that Given pulled off a stupendous point-blank save, thrusting out a hand to his left and diverting the ball around the post for a corner.
A minute later Ljungberg crossed from the same flank and Henry, under pressure from Boumsong, miskicked at the far post.
Arsenal were starting to knock the ball around with confidence and retain possession with ease. The "olè's" even sprung forth from the visiting fans at one point as their side kept the ball for minutes.
Henry nearly twisted himself some space after the half hour but Boumsong dispossessed him at the vital second. Just before the break, Ljungberg inadvertently blocked Van Persie's goalbound shot.
Inbetween those efforts, the excellent Shola Ameobi fed Michael Owen and the England striker's low ball trundled unconverted across the Arsenal six-yard box.
Newcastle were a transformed side after the interval. They started throwing crosses and free-kicks into the area. Lehmann punched clear from Solano's effort and Scott Parker thumped a pair of long-range shots over the bar.
However the game changed on the hour, Gilberto was fooled by Boumsong and the Brazilian caught the French international with his trailing leg. Referee Gallagher brandished a yellow card to Gilberto, who had been booked on the stroke of half time for a foul on Ameobi. The second card meant he was off.
Wenger immediately withdrew Hleb for Flamini. The presumably the idea was to stiffen a midfield now reduced to three players.
The numerical advantage allowed Newcastle to assume total control, although the loss of the influential Parker through injury did affect their fluency in the latter stages.
If anything Arsenal looked to have weathered the storm when the goal came. The ball was pin-balling around their area and the visitors failed to clear. Eventually Shearer found Solano on the right and Solano found the net.
The visitors threw on Quincy and Robert Pires but could not muster a clear chance to equalise.
They have now taken just five points from a possible 28 away from home in the Premiership.
Referee: Dermot Gallagher
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