Bukayo Saka and Gabriel Martinelli were on target as Arsenal moved level on points with fourth-placed West Ham with a 2-0 victory over Newcastle, who had Eddie Howe in the dugout for the first time.
Both goals came in 10 second-half minutes after a cagey opening period in which Arsenal should have led.
Their best chance came on the stroke of half-time when Saka's cross was attacked by Emile Smith Rowe whose bullet header was brilliantly saved by Martin Dubravka but from three yards out Pierre-Emerick Aubameyang could only hit the post with the rebound.
Howe - who missed the 3-3 draw with Brentford last weekend following a positive Covid-19 test - would have been pleased with his side's start but it could have been even better only for Aaron Ramsdale, who made a superb save, tipping Jonjo Shelvey's curler onto the crossbar.
Newcastle defended resiliently but they were carved open 11 minutes after the restart as Arsenal took the lead following a lovely team move. After 14 passes, Nuno Tavares played in Saka who finished with aplomb from an acute angle.
Sadly, the goalscorer was forced to come off moments later with an apparent hip problem. But his replacement Martinelli made an immediate impact, scoring with just second touch as he lifted the ball over the on-rushing Dubravka from Takehiro Tomiyasu's pass less than two minutes after coming on.
Newcastle toiled in search of a way back but couldn't find the goal that would have set up an intriguing finale and they remain bottom without a victory this season. They now prepare for a huge match against fellow strugglers Norwich on Tuesday night.
As for Arsenal, a trip to Old Trafford follows on Thursday.