Arsenal moved into seventh place in the Premier League with a 2-0 victory over West Brom on Monday.
Alexandre Lacazette scored both goals at the Emirates Stadium to give Arsene Wenger's side a third league win of the season and a seventh in a row at home to the Baggies.
Tony Pulis' side won the last meeting between these teams in March and had their chances to claim at least a share of the spoils, with Jay Rodriguez hitting the post and Jake Livermore failing to convert the rebound before Lacazette headed in the opener.
West Brom, for whom Gareth Barry made a record 633rd Premier League appearance, continued to threaten an unconvincing Arsenal defence but their lack of composure in attack was compounded when Lacazette's penalty doubled the lead.
The goal made the Gunners' club-record signing the first man to score in his first three Premier League matches at home and allowed them to ease to the win, which lifts them back to within six points of league leaders Manchester City.
They now turn their attentions to Thursday's Europa League trip to Belarus, where they will meet BATE in their second Group H match.
Alexis Sanchez, starting in support of Lacazette in attack, flashed a free-kick narrowly wide of the right-hand post early on but West Brom should have taken the lead inside 10 minutes.
Rodriguez raced in behind Shkodran Mustafi, who floored him with a poorly timed tackle inside the penalty area, but the forward chose to play on and saw a low shot tipped onto the post by Petr Cech, before Livermore scuffed the rebound wide.
It was a miss for which West Brom were made to pay. From another free-kick, Sanchez saw a shot tipped onto the crossbar by Ben Foster, allowing Lacazette to head home the rebound and become the first Arsenal player to score in his first three home league appearances since Brian Marwood in September 1988.
3 - A. Lacazette is the first Arsenal player to score in his first 3 home league apps for the club since Brian Marwood in Sept 1988. Gunner. pic.twitter.com/9Q8pwxwTEc-- OptaJoe (@OptaJoe) September 25, 2017
The Gunners were comfortably in control but Rodriguez missed a terrific chance to snatch an equaliser before half-time, heading Grzegorz Krychowiak's cross beyond Cech only to see Nacho Monreal hook his rather weak effort off the line.
West Brom's pressure continued and Rodriguez again failed to convert from close range after Barry cushioned a header back into his path, but only a timely block from former Arsenal man Kieran Gibbs stopped Lacazette slotting home his second of the match five minutes after the break.
Arsenal began to assume greater control and they were rewarded for their more positive approach with 66 minutes played. Allan Nyom bundled Aaron Ramsey over near the byline after the Wales man surged past him into the box, allowing Lacazette to fire his penalty just past Foster's reach and into the bottom-right corner - the Gunners' 100th converted spot kick in the Premier League.
Nyom sarcastically applauded Bobby Madley's decision, with West Brom players clearly still aggrieved not to have been awarded a penalty of their own in the same area, and their resistance appeared to have been broken at last as the hosts cruised through the closing minutes to claim the points.