Arsenal came into this game on the back of defeats to Everton and Villarreal. Manager Mikel Arteta made several changes to his starting lineup, with one eye on Thursday's make-or-break second leg of Arsenal's Europa League semi-final against the Spanish side.
The likes of Bukayo Saka, Emile Smith Rowe, Nicolas Pepe and Bernd Leno dropped to the bench, while Pierre-Emerick Aubameyang made his first start in a month.
Arsenal started the game on the front foot and deservedly went ahead through Mohamed Elneny's smart half-volley from the edge of the box.
Some good interplay down the right-wing saw Hector Bellerin send a cross into the area, but Aubameyang squandered the opportunity. But the rebound fell to Elneny, who made no mistake to score his first Premier League goal.
Arsenal dominated proceedings for the rest of the first half, as Newcastle rarely threatened, although Allan Saint-Maximin proved to be a handful for the visitors.
Mohamed Elneny almost got a second but saw his goal-bound header cleared off the line by Miguel Almiron, while Granit Xhaka received a booking for a cynical challenge.
Arsenal were undoubtedly the better side in the opening 45 minutes and arguably should have had a more convincing lead to show for their dominance.
The second half was a more balanced affair, as the hosts grew into the game, but Steve Bruce's side lacked conviction in the final third to make their mounting pressure count.
Arsenal doubled their lead in the 66th minute when Odegaard played Martinelli down the flanks. The Brazilian subsequently sent a delightful cross to the back-post, which Aubameyang finished acrobatically.
The hosts were reduced to ten men when substitute Fabian Schar was shown a straight red card for a studs-on challenge on Martinelli. Arsenal saw out the victory to climb to ninth in the league table ahead of their marquee clash with Villarreal.
On that note, let's have a look at the ratings of Arsenal players in the game.
Matt Ryan - 6.5/10
The Arsenal goalkeeper was a relative spectator for most of the game but showed good reflexes to save Saint Maximin's attempted lob in the first half.
Granit Xhaka - 6.5/10
Granit Xhaka was solid once again in both halves in his new-found role at left-back. He was lucky to escape a second booking for a rash challenge, though.
Gabriel Magalhaes - 6/10
Newcastle's lack of attacking verve meant Gabriel Magalhaes did not have too much defensive work to do. Nevertheless, he stepped up on a few occasions when he was needed.
David Luiz - 7.5/10
David Luiz played a key role in launching Arsenal's attacks with his long diagonal passes. He pulled up with a hamstring injury early in the second half and had to be substituted, though.
Hector Bellerin - 6.5/10
Hector Bellerin offered a lot going forward, but he was susceptible defensively, and Newcastle focused most of their attack down his flank.
Dani Ceballos - 6/10
Real Madrid loanee Dani Ceballos helped shield the Arsenal defence and also contributed in attack.
Mohamed Elneny - 8/10
Mohamed Elneny showed great technique to score Arsenal's opener and was unlucky to see a goal-bound header cleared off the line.
The 19-year-old was full of running and proved to be a handful for the Newcastle defence. Gabriel Martinelli's directness proved too much to handle for Jacob Murphy, and he also provided the assist for Arsenal's second goal.
Martin Odegaard - 7/10
Martin Odegaard was less involved in the second half, but his killer through-ball put Martinelli on his way to assisting Aubameyang.
Willian - 6.5/10
Willian created a few chances for Arsenal with his set-pieces and also put in a decent defensive shift for the visitors.
Pierre-Emerick Aubameyang - 7/10
The Arsenal captain was on the periphery for most of the game, but Pierre-Emerick Aubameyang showed his predatory instincts to score his first goal for the club in almost two months.
Ratings of Arsenal Substitutes:
Callum Chambers - 6/10
Callum Chambers came on for David Luiz in the 53rd minute and played his role in helping Arsenal keep a clean sheet.
Nicolas Pepe - 6/10
The in-form Nicolas Pepe was afforded 12 minutes to warm up for Villarreal, and he caused some problems for in this game as well.
Thomas Partey - 6/10
Thomas Partey came on in the 85th minute and registered an impressive pass accuracy of 82.4%