A superbly-executed volley from Mesut Ozil gave us all three points in a nervy encounter at Emirates Stadium.
The German playmaker demonstrated typical poise and technique, latching onto a defensive header just inside the area to score the only goal of the game.
We had plenty of chances to kill the game off after that, as we enjoyed more than 70 per cent possession, but we almost paid for our wastefulness in front of goal late on.
The visitors rallied in the final 10 minutes, but we stood firm to record our first win in four Premier League games.
The team showed just one change from the frustrating goalless draw at West Ham on Wednesday, and we continued where we left off against the Hammers - dominating possession and probing for openings.
The first chance fell to Hector Bellerin. A wonderful first-time Alexis flick fed the advancing Alexandre Lacazette inside the area, and his shot was only half cleared into Bellerin's path. The ball fell to his weaker left foot though, and his shot was charged down for a corner.
Alexis then flashed a shot over the bar, but the game was being played at a fairly sedate pace until Ainsley Maitland-Niles injected some verve. The 20 year old, who had retained his place at left back, won the ball in midfield, beat two players with a marauding run, and shot just wide from the edge of the box. The shot rippled the side-netting as the home crowd were ready to acclaim a moment of magic from the England youth international.
Midway through the half, a man much more used to providing the spectacular, did break the deadlock. Newcastle cleared the danger, under pressure from Alexis, but Florian Lejeune's header fell as far as Ozil just inside the area. The German steadied himself, adjusted his body, and fired a first-time volley, guided beyond the despairing Rob Elliot.
Shortly afterwards Bellerin tried a volley of his own at the far post, but he couldn't keep his attempt down.
We were playing with a bit more freedom now, and continued to create chances.
Granit Xhaka shot wide from 20 yards before Ozil was denied at the near post having broken behind the overworked Newcastle defence with a neat one-two with Lacazette.
Alex Iwobi had an effort desperately clawed away by Elliot, and Lacazette blazed over the bar as we continued to chip away, searching for the crucial second goal.
Newcastle, although struggling to get on the ball, were still in the contest, and Jacob Murphy forced a good low save from Petr Cech in a rare foray forward.
Iwobi set up Lacazette at the other end, but the Frenchman chose to lift the ball over Elliot, rather than go for power, and got too much height on the lob.
Chances continued to come and go. Iwobi's weak finish didn't match his neat footwork to create the opening, and Wilshere shot straight at the keeper from Giroud's knockdown.
Laurent Koscielny headed wide from the corner and we so nearly paid for our lack of ruthlessness when Joselu tried his luck from the edge of the area – his deflected shot wrong footed Cech before trickling wide.
Newcastle were on top now - the one-goal lead was looking precarious as we entered the final ten minutes. But Cech claimed a couple of dangerous crosses and in the end the defence did enough to see out the win.
HOW IT HAPPENED
What it means
The win lifted us into fourth-place, at least temporarily, as we made it eight wins out of nine at home in the league this season. Petr Cech also kept his 199th Premier League clean sheet in the process.
This was the first of three home games in seven days. Next up it's West Ham on Tuesday night in the Carabao Cup, before we host Liverpool in the Premier League on Friday night.
For the second game in a row, Arsenal academy product Ainsley Maitland-Niles started at left back in a back four.
Here are the highlights from the 20-year-old, who was making just his second Premier League start.
14 - He anticipated brilliantly to intercept the ball in midfield. He then skipped past two challenges with a driving run before firing just wide of the upright with a low right-footed effort.
16 - Again in an advanced position, he centred for Lacazette but Rob Elliot snuffed out the chance.
32 - Keen to support the attack again, Ainsley swapped passed with Alexis just outside the area, but was disposed by Jamaal Lascelles.
42 - Defensive work this time from Ainsley, seeing out a developing attack for a corner.
68 - Ainsley continues to link up well with Alexis, as he is almost constantly positioned in the opposition half.
87 - Swapping passes with Jack Wilshere on the left flank, helping to relieve some pressure.
90 - The youngster showed excellent discipline to record a second consecutive clean sheet. He made three clearances, two interceptions and one tackle in the 90 minutes, with an 89 per cent pass completion rate.
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