The Gunners fielded a strong XI against a Baggies side who made 11 changes from their weekend win over Blackburn Rovers, with Valerien Ismael handing chances to a number of fringe and youth players at The Hawthorns.
Despite an initially shaky start to the game, Arsenal soon found their groove and eased to a 6-0 success on the night thanks to Pierre-Emerick Aubameyang's hat-trick alongside goals from Nicolas Pepe, Bukayo Saka and Alexandre Lacazette.
Now, Arsenal have been rewarded with a home tie against AFC Wimbledon in the third round, which takes place the week commencing September 20, and that tie will mark the first ever competitive meeting between the two clubs.
Following the victory, Arsenal skipper Aubameyang insisted that every Gunners player is '100% committed' after a difficult two weeks in the Premier League, and the 32-year-old is hopeful that Wednesday's drubbing can boost the confidence in Mikel Arteta's ranks.
The Gunners will now prepare for Saturday's trip to Premier League champions Manchester City after back-to-back 2-0 defeats against Brentford and Chelsea earlier this month.
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