- Alexandre Lacazette at the double as Arsenal maintain 100% home record in 2017-18 and wrap up a seventh successive league win on their own patch
- French striker heads home rebound after Alexis Sanchez's free-kick is saved by Ben Foster
- Lacazette doubles his tally from the spot in the second half after Aaron Ramsey is barged over by Allan Nyom
- Record signing becomes the first Gunners player to score in his first three home matches since Brian Marwood in September 1988
- Jay Rodriguez hits the post after being denied a clear penalty by referee Robert Madley following a mistimed challenge from Shkodran Mustafi
- West Brom spurn plenty of chances to equalise before the break
- Veteran Baggies midfielder Gareth Barry makes a record-breaking 633rd Premier League appearance in north London after equalling Ryan Giggs' mark in a goalless draw with West Ham last weekend
That is it from me for tonight, thanks for following along and keep your eyes peeled for post-match reaction from IBTimes UK's man on the ground, Eduardo Fernandez-Abascal.
We will be back tomorrow evening to bring you live coverage of matchday two of the Champions League, with Tottenham, Liverpool, Manchester City and holders Real Madrid all in action.
Until then, it's goodbye.
Arsenal now sit seventh in the Premier League table, one point adrift of the top four and six behind leaders Manchester City. They host newly-promoted Brighton next after a long Europa League trip to Belarus on Thursday evening.
West Brom, meanwhile, have now gone five matches without a win in all competitions and lie 12th before Saturday's visit of Watford to The Hawthorns.
A fairly routine win in the end for Arsenal, who maintain their 100% home record in 2017-18 and rack up a seventh successive Premier League victory on their own turf.
They lived very dangerously during an eventful first half, but totally controlled proceedings after the interval and got the second goal they needed to put the game to bed.
Pulis is likely to fume about referee Madley's decision not to award his team a penalty at 0-0. His overall record at the Emirates Stadium now stands at 10 defeats from 10 matches, with 22 goals conceded and only three scored.
Indeed, West Brom have now lost each of their last seven visits to this ground.
Arsenal 2-0 West Brom
Rondon is fouled and Maitland-Niles finally replaces Ramsey. The versatile 20-year-old will only be on the pitch for a matter of seconds.
Maitland-Niles has been waiting patiently to enter the fray for a while but it does not look like he'll get that opportunity with time running out.
Ramsey shoots straight at Foster after being teed up by Giroud. Three minutes of added time to be played at the Emirates.
Giroud takes down a great pass from Elneny and sets up Xhaka for a shot that is drilled over the crossbar.
Five minutes plus stoppage time remaining and West Brom, despite their first half efforts, now look well beaten. They have not been able to muster the same sort of enthusiasm after the break and the second goal killed this as a contest.
Arsenal work the short corner and Bellerin's powerful shot is deflected behind by the head of Rodriguez.
Wenger does finally look to his bench in the final 10 minutes, sending on Giroud and Ozil in place of Lacazette and Sanchez.
The home fans call for a second yellow for Dawson after the West Brom defender commits another foul on Sanchez.
Referee Madley instead opts for a final warning.
Krychowiak dispossesses Monreal with a well-timed sliding challenge. Sanchez then curls an effort straight at Foster.
Still no changes from Wenger, who must be content with what he is seeing. Arsenal travel to BATE Borisov in the Europa League on Thursday before hosting Brighton on Sunday lunchtime.
Sanchez with an exquisite touch and pass under severe pressure from Dawson. Xhaka then lets fly from distance but fails to test Foster.
Phillips for Nyom is West Brom's final change.
Looking for his first hat-trick in English football, Lacazette takes down Sanchez's cross before firing into row z from a tight angle.
Cech then thwarts Rondon's purposeful run at the other end.
Reliable. That was also Arsenal's 100th penalty in the Premier League, per Opta Sports.
Foster guesses correctly low to his left, but is unable to get a hand to Lacazette's well-struck effort into the bottom corner.
Some much-needed breathing space for Arsenal with just over 20 minutes remaining. West Brom now have a mountain to climb.
Goal: Arsenal 2-0 West Brom (Alexandre Lacazette)
Ramsey turns Nyom down the Arsenal left and is then unceremoniously barged over by the Cameroonian right-back.
Lacazette steps up from 12 yards...
Penalty to Arsenal
A second substitution in quick succession for West Brom. Salomon Rondon, who has scored only one goal in his last 25 appearances, replaces Robson-Kanu.
Pulis' first change of the evening sees Livermore make way for Scotland midfielder Morrison.
Decisive goalkeeping from Cech to come out and emphatically punch clear a West Brom free-kick.
Lovely skill from Sanchez to shake off the attentions of Livermore. Ramsey is unable to bring down his subsequent cross and the ball makes its way back to Foster off Evans.